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 A344917 #7 Jul 09 2021 14:58:49 %S A344917 1,1,-1,-7,5,31,-61,-127,1385,511,-50521,-1414477,2702765,8191, %T A344917 -199360981,-118518239,19391512145,5749691557,-2404879675441, %U A344917 -91546277357,370371188237525,162912981133,-69348874393137901,-1982765468311237,15514534163557086905,22076500342261 %N A344917 a(n) = numerator(4^(n + 1)*zeta(-n, 1/4)). %F A344917 a(n)/A344918(n) - 2*A092440(n)*zeta(-n) = -A163982(n) for n >= 0. %e A344917 Rational sequence starts: 1, 1/6, -1, -7/60, 5, 31/126, -61, -127/120, 1385, ... %p A344917 seq(numer(4^(n+1)*Zeta(0, -n, 1/4)), n=0..25); %o A344917 (SageMath) %o A344917 def a(n): return 4^(n+1)*hurwitz_zeta(-n, 1/4) if n > 0 else 1 %o A344917 print([a(n).numerator() for n in (0..25)]) %Y A344917 Cf. A344918 (denominators), A092440, A163982. %K A344917 sign,frac %O A344917 0,4 %A A344917 _Peter Luschny_, Jul 09 2021