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 A087763 #14 Jul 19 2022 01:20:34 %S A087763 2,3,5,13,19,23,37,41,43,47,53,59,61,67,71,73,83,89,97,101,103,107, %T A087763 109,127,137,149,151,157,163,167,173,179,181,191,193,197,199,211,223, %U A087763 227,229,233,239,241,251,257,263,269,271,277,281,283,293,307,311,313,317 %N A087763 Primes p such that 8^p - 7^p is composite. %t A087763 Select[Prime[Range[70]],CompositeQ[8^#-7^#]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Mar 15 2018 *) %o A087763 (PARI) apmb(a,b,n) = { forprime(x=2,n, y=a^x-b^x; if(!ispseudoprime(y), print1(x","); ) ) } %Y A087763 Cf. A016177. %Y A087763 Primes p such that k^p - (k-1)^p is composite: A087489 (k=3), A087490 (k=4), A087685 (k=5), A087749 (k=6), A087759 (k=7), this sequence (k=8), A087894 (k=9), A087895 (k=10). %K A087763 nonn %O A087763 1,1 %A A087763 _Cino Hilliard_, Oct 26 2003 %E A087763 Offset corrected by _Mohammed Yaseen_, Jul 18 2022