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 A087895 #24 Jul 19 2022 01:33:42 %S A087895 5,13,17,23,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107, %T A087895 109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197, %U A087895 199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293 %N A087895 Primes p such that 10^p - 9^p is composite. %t A087895 Select[Prime[Range[100]],!PrimeQ[10^#-9^#]&] (* _Harvey P. Dale_, Jun 21 2012 *) %o A087895 (PARI) apmb(a,b,n) = { forprime(x=2,n, y=a^x-b^x; if(!ispseudoprime(y), print1(x","); ) ) } %Y A087895 Cf. A016189, A062576. %Y A087895 Primes k such that x^k - (x-1)^k is composite: A087489 (x=3), A087490 (x=4), A087685 (x=5), A087749 (x=6), A087759 (x=7), A087763 (x=8), A087894 (x=9), this sequence (x=10). %K A087895 nonn %O A087895 1,1 %A A087895 _Cino Hilliard_, Oct 26 2003 %E A087895 Offset corrected by _Mohammed Yaseen_, Jul 19 2022