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A280656
Denominator of (Sum_{k=0..n^2-1} (-1)^k*sqrt(Pi)/(Gamma(1/2-k)*Gamma(1+k))) - n.
2
1, 16, 32768, 67108864, 70368744177664, 147573952589676412928, 19807040628566084398385987584, 1329227995784915872903807060280344576, 365375409332725729550921208179070754913983135744, 25108406941546723055343157692830665664409421777856138051584
OFFSET
1,2
COMMENTS
a(n) is a power of 2.
FORMULA
a(n)=Denominator of Sum_{k=0..n^2-1}(Binomial(2k,k)/4^k)-n.
MATHEMATICA
Denominator[Table[Sum[Binomial[2k, k]/4^k, {k, 0, n^2-1}]-n, {n, 1, 10}]]
CROSSREFS
Cf. A280655 (numerators).
Sequence in context: A087518 A249971 A221244 * A265662 A253912 A017548
KEYWORD
nonn,frac
AUTHOR
Ralf Steiner, Apr 12 2017
STATUS
approved