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 A129518 #13 Jun 08 2021 02:24:20 %S A129518 3,7,47,59,79,83,103,107,127,139,191,199,211,251,263,283,307,331,367, %T A129518 379,383,431,467,479,499,503,547,587,599,607,631,643,659,727,743,811, %U A129518 823,827,839,859,863,883,887,907,971,991,1087,1151,1163,1171,1259,1283 %N A129518 Numbers k > 2 such that k divides (k-2)!! - 1 and (k-3)!! - 1. %C A129518 All terms are primes of the form 4m+3 belonging to A002145. A002145 is the union of this sequence and A129517 (odd primes p such that p divides (p-1)!! - 1). %C A129518 Odd numbers k > 1 such that k divides (k-1)!! + 1. - _Thomas Ordowski_, Jul 26 2016 %t A129518 Select[Range[3,2000],IntegerQ[((#-2)!!-1)/# ]&&IntegerQ[((#-3)!!-1)/# ]&] %Y A129518 Cf. A006882 (double factorials). %Y A129518 Cf. A002145 (primes of form 4k+3). %Y A129518 Cf. A129517 (odd primes p such that p divides (p-1)!! - 1). %Y A129518 Cf. A129516 (numbers k such that k divides (k-1)!! - 1). %Y A129518 Cf. A260298. %K A129518 nonn %O A129518 1,1 %A A129518 _Alexander Adamchuk_, Apr 18 2007