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A157115
Alternate terms of A007519, A007520, A007521, A007522.
1
17, 3, 5, 7, 41, 11, 13, 23, 73, 19, 29, 31, 89, 43, 37, 47, 97, 59, 53, 71, 113, 67, 61, 79, 137, 83, 101, 103, 193, 107, 109, 127, 233, 131, 149, 151, 241, 139, 157, 167, 257, 163, 173, 191, 281, 179, 181, 199, 313, 211, 197, 223, 337, 227, 229, 239, 353, 251, 269
OFFSET
1,1
COMMENTS
Or, read the following table by columns:
17,41,73,89,97,113,137,193,233,241,257,281,313,337,353,401,409,... (primes = = 1 mod 8)
3,11,19,43,59,67,83,107,131,139,163,179,211,227,251,283,307,331,... (primes == 3 mod 8)
5,13,29,37,53,61,101,109,149,157,173,181,197,229,269,277,293,317,... (primes == 5 mod 8)
7,23,31,47,71,79,103,127,151,167,191,199,223,239,263,271,311,359,... (primes == 7 mod 8)
EXAMPLE
The first four primes congruent to (1,3,5,7) mod 8 are 17,3,5,7, hence a(1..4)=17,3,5,7;
The next four primes congruent to (1,3,5,7) mod 8 are 41,11,13,23, hence a(5..8)=41,11,13,23, etc.
MATHEMATICA
s[i_]:=(c=0; a=2*i-1; Reap[Do[If[PrimeQ[a], c++; Sow[a]]; If[c>99, Break[], a = a+8], {10^8}]][[2, 1]]); Flatten[Transpose[Table[s[i], {i, 4}]]]; (* Zak Seidov, Jan 16 2013 *)
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Zak Seidov and N. J. A. Sloane, Feb 23 2009
STATUS
approved