A280656 Denominator of (Sum_{k=0..n^2-1} (-1)^k*sqrt(Pi)/(Gamma(1/2-k)*Gamma(1+k))) - n.

1, 16, 32768, 67108864, 70368744177664, 147573952589676412928, 19807040628566084398385987584, 1329227995784915872903807060280344576, 365375409332725729550921208179070754913983135744, 25108406941546723055343157692830665664409421777856138051584

Offset: 1

Author

Ralf Steiner, Apr 12 2017

Keywords

• nonn
• frac

Comments

a(n) is a power of 2.

Crossrefs

Cf. A280655 (numerators).

Programs

Mathematica

Denominator[Table[Sum[Binomial[2k,k]/4^k,{k,0,n^2-1}]-n,{n,1,10}]]

Formula

a(n)=Denominator of Sum_{k=0..n^2-1}(Binomial(2k,k)/4^k)-n.