This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A064908 #19 Apr 16 2018 19:11:37 %S A064908 299,473,551,1037,1199,1271,1273,1313,1441,1651,1739,1817,2167,2279, %T A064908 2327,2651,2771,2813,2893,3193,3341,3349,3377,3439,3679,4103,4331, %U A064908 4829,4883,5071,5707,5977,6049,6059,6239,6281,6383,6523,6817,7031,7037,7097 %N A064908 Semiprimes p1*p2 such that p2 mod p1 = 10, with p2 > p1. %H A064908 John Cerkan, <a href="/A064908/b064908.txt">Table of n, a(n) for n = 1..10000</a> %o A064908 (Python) %o A064908 from sympy import factorint %o A064908 def is_A064908(n): %o A064908 f = factorint(n) %o A064908 return (sum([f[i] for i in f]) == 2) and (max(f) % min(f) == 10) # _John Cerkan_, Apr 14 2018 %o A064908 (PARI) isok(n) = my(f = factor(n)); (#f~ == 2) && (vecmax(f[,2]) < 2) && ((f[2,1] % f[1,1]) == 10); \\ _Michel Marcus_, Apr 16 2018 %Y A064908 Cf. A001358 (p2 mod p1 = 0), A064899-A064911. %K A064908 nonn %O A064908 1,1 %A A064908 _Patrick De Geest_, Oct 13 2001 %E A064908 Offset changed by _John Cerkan_, Apr 12 2018