A281264 - OEIS

A281264

Base-2 logarithm of denominator of (Sum_{k=0..n^2-1} (-1)^k*sqrt(Pi)/(Gamma(1/2-k)*Gamma(1+k))) - n.

0, 4, 15, 26, 46, 67, 94, 120, 158, 194, 236, 281, 333, 386, 445, 502, 574, 642, 716, 792, 875, 960, 1054, 1143, 1244, 1345, 1451, 1560, 1676, 1793, 1916, 2036, 2174, 2306, 2444, 2584, 2731, 2880, 3034, 3190, 3356, 3519, 3690, 3862, 4041, 4226, 4413, 4597, 4796, 4992

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..50.

MATHEMATICA

f[n_] := Log2[ Denominator[ Sum[ Binomial[2m, m]/4^m, {m, 0, n^2 -1}] -n]]; Array[f, 50]

CROSSREFS

Cf. A280656, A007814.

Sequence in context: A063129 A061873 A017437 * A372237 A366869 A267103

Adjacent sequences: A281261 A281262 A281263 * A281265 A281266 A281267

KEYWORD

nonn

AUTHOR

Ralf Steiner, Apr 13 2017

STATUS

approved