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User:J. W. Helkenberg
- Python Program to Produce Primes
I wish to publish this sequence, which I think is interesting.
1, 4, 5, 8, 10, 12, 14, 15, 16, 19, 21, 22, 23, 27, 27, 27, 29, 30, 32, 35, 36, 38, 40, 42, 43, 43, 44, 46, 48, 49 ,50, 52, 53, 56, 57, 58, 59, 60, 61, 61, 63, 64, 66, 67, 71, 71, 71, 75, 77, 78, 78, 78, 79, 80, 81, 82, 82, 83, 85, 87, 88, 92, 92, 92, 92, 93, 95, 99, 99, 99, 103, 104, 104, 104, 105, 106, 106, 106, 111, 112, 113, 114, 115, 116, 118, 118, 118, 120, 122, 126, 127, 127, 127, 128, 129, 131, 132, 134, 135, 137, 137, 137, 141, 141, 141
This program generates one sequences and derives a second sequence. The first sequence it generates lists all composite numbers of the form 90n+1 (beneath a limit) and then sorts these values ascending. The second list is generated by an algorithm that identifies numbers missing from the first list. It returns these numbers as a separate output. You will be prompted for the output.
The first list is contradistinct from the second list. The second list = Sloane's A181732. See https://oeis.org/A181732
The limits in the program are set to extend terms to match the largest member of the bfile for A181732. See https://oeis.org/A181732/b181732.txt
#!/usr/local/env python #python 2.7 import sys import csv import time import subprocess dump = open("composite1.csv", "w") new_test = 40000 #this is a limit def dr1_ld1_91_91(x): ..y = 90*(x*x) + 2*x ..#print "91", y ..dump.write(str(y) + "\n") ..for n in range(1, new_test): ....new_y = y+((91+(90*(x-1)))*n) ....#print "91", new_y ....dump.write(str(new_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_19_19(x): ..y = 90*(x*x) - 142*x + 56 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+ ((19+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_37_73(x): ..y = 90*(x*x) - 70*x + 10 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((37+(90*(x-1)))*n) ....new2_y = y+((73+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_11_41(x): ..y = 90*(x*x) - 128*x + 43 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((11+(90*(x-1)))*n) ....new2_y = y+((41+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_29_59(x): ..y = 90*(x*x) - 92*x + 21 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((29+(90*(x-1)))*n) ....new2_y = y+((59+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_47_23(x): ..y = 90*(x*x) - 110*x + 32 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((23+(90*(x-1)))*n) ....new2_y = y+((47+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_77_83(x): ..y = 90*(x*x) - 20*x + 1 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((77+(90*(x-1)))*n) ....new2_y = y+((83+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_7_13(x): ..y = 90*(x*x) - 160*x + 71 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((7+(90*(x-1)))*n) ....new2_y = y+((13+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_31_61(x): ..y = 90*(x*x) - 88*x + 19 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((31+(90*(x-1)))*n) ....new2_y = y+((61+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_49_79(x): ..y = 90*(x*x) - 52*x + 5 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((49+(90*(x-1)))*n) ....new2_y = y+((79+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_43_67(x): ..y = 90*(x*x) - 70*x + 12 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((43+(90*(x-1)))*n) ....new2_y = y+((67+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_17_53(x): ..y = 90*(x*x) - 110*x + 30 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((17+(90*(x-1)))*n) ....new2_y = y+((53+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....dump.write(str(new2_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_71_71(x): ..y = 90*(x*x) - 38*x + 4 ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((71+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass def dr1_ld1_89_89(x): ..y = 90*(x*x) - 2*x ..dump.write(str(y) + "\n") ..for n in range (1, new_test): ....new_y = y+((89+(90*(x-1)))*n) ....dump.write(str(new_y) + "\n") ....if new_y > new_test: ......return ....else: ......pass for x in xrange(1, 90): #This is a limit. ....dr1_ld1_7_13(x) #1 @xrange(x) = 22, y = 1814 ....dr1_ld1_19_19(x) #4 ....dr1_ld1_11_41(x) #5 ....dr1_ld1_17_53(x) #10 ....dr1_ld1_47_23(x) #12 ....dr1_ld1_29_59(x) #19 ....dr1_ld1_31_61(x) #21 ....dr1_ld1_37_73(x) #30 ....dr1_ld1_43_67(x) #32 ....dr1_ld1_49_79(x) #43 ....dr1_ld1_71_71(x) #56 ....dr1_ld1_77_83(x) #71 ....dr1_ld1_89_89(x) #88 ....dr1_ld1_91_91(x) #92 def bash_command(cmd): ....subprocess.Popen(cmd, shell=True) bash_command('sort -n composite1.csv -o composite2.csv') time.sleep(0.2) #make sure subprocess has finished z=890 f=open("composite2.csv") for i in range(z): ..line=f.next().strip() ..print line ..#print "not prime", line f.close() proceed = raw_input("Shall we print the prime sequence for 90n+1? "yes" or "no"") if proceed == "yes": ..pass if proceed == "no": ..quit("goodbye") #run this code to compare to https://oeis.org/A181732/b181732.txt with open("composite2.csv") as f: ....rd=f.readlines() ....x=[t.strip("\n") for t in rd] ....for i in range(0, 37188): ........if str(i) not in x: ............print ("{} is prime".format(i))