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 A344917 a(n) = numerator(4^(n + 1)*zeta(-n, 1/4)). 1
 1, 1, -1, -7, 5, 31, -61, -127, 1385, 511, -50521, -1414477, 2702765, 8191, -199360981, -118518239, 19391512145, 5749691557, -2404879675441, -91546277357, 370371188237525, 162912981133, -69348874393137901, -1982765468311237, 15514534163557086905, 22076500342261 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS FORMULA a(n)/A344918(n) - 2*A092440(n)*zeta(-n) = -A163982(n) for n >= 0. EXAMPLE Rational sequence starts: 1, 1/6, -1, -7/60, 5, 31/126, -61, -127/120, 1385, ... MAPLE seq(numer(4^(n+1)*Zeta(0, -n, 1/4)), n=0..25); PROG (SageMath) def a(n): return 4^(n+1)*hurwitz_zeta(-n, 1/4) if n > 0 else 1 print([a(n).numerator() for n in (0..25)]) CROSSREFS Cf. A344918 (denominators), A092440, A163982. Sequence in context: A213246 A213243 A185269 * A328758 A070426 A341431 Adjacent sequences:  A344914 A344915 A344916 * A344918 A344919 A344920 KEYWORD sign,frac AUTHOR Peter Luschny, Jul 09 2021 STATUS approved

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Last modified September 27 12:40 EDT 2021. Contains 347688 sequences. (Running on oeis4.)