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A160337
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1 plus primes using only digits {0, 1, 2, 3, 5, 7}.
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0
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1, 2, 3, 5, 7, 11, 13, 17, 23, 31, 37, 53, 71, 73, 101, 103, 107, 113, 127, 131, 137, 151, 157, 173, 211, 223, 227, 233, 251, 257, 271, 277, 307, 311, 313, 317, 331, 337, 353, 373, 503, 521, 523, 557, 571, 577, 701, 727, 733, 751, 757, 773, 1013, 1021, 1031
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OFFSET
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1,2
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COMMENTS
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Since the first 5 primes numbers are 1,2,3,5,7 (1 included), so the rest of the numbers can be generated by using numbers from the set {0,1,2,3,5,7} as every digit must be a prime number as well.
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LINKS
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Table of n, a(n) for n=1..55.
Young Programmer,Problem Set Problem 13
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EXAMPLE
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For n = 3 the solutions are ... 1,2,3
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PROG
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(Other) /* * Author : Mohit Singh Kanwal * Language : C++ * an example program to generate first 100 prime numbers where each digit is also a prime number * National University of Singapore * 2009-2010 */ #include <iostream> #include <stdio.h> #include <fstream> #include <conio.h> using namespace std; /* */ bool isPrime(long n) { if(n==0) return true; for(long i = 2; i<=n/2; i++) { if(n%i == 0) return false; } return true; } bool checkdigit(long n) { bool falg = true; long no = n; while(no>0) { long digit = no%10; // if(digit==0) return false; // else { if(!isPrime (digit)) return false; } no = no/10; } return true; } int main() { // ofstream out; // out.open("ANS.txt"); long limit = 1000000000; int count =0; for(long i=1; i<=limit; i++) { if(isPrime(i) && checkdigit(i)) { count++; cout<<i<<endl; } if(count == 100) { getch(); return 0; } } getch(); return 0; }
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CROSSREFS
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Cf. A012884, A143390
Sequence in context: A143390 A038617 A036962 * A190222 A012884 A068669
Adjacent sequences: A160334 A160335 A160336 * A160338 A160339 A160340
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KEYWORD
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nonn,base
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AUTHOR
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Mohit Singh Kanwal (mohit_kanwal(AT)hotmail.com), May 10 2009
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STATUS
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approved
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