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A276240 a(n) = denominator of rational fraction of function Gamma[5/4]^2 Gamma[n + 3/4]^2/(Gamma[3/4]^2 Gamma[n + 5/4]^2). 2
1, 25, 225, 38025, 48841, 439569, 274730625, 25672050625, 25672050625, 1405801492225, 13983149754025, 349578743850625, 17129358448680625, 166492622430255625, 6659704897210225, 24780761922519247225, 2136708553523343255625, 2136708553523343255625, 11386519881725896209225625, 892703158727310262803289 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
From Robert Israel, Sep 09 2016: (Start)
Square of denominator of pochhammer(3/4,n)/pochhammer(5/4,n) = Product_{odd k <= 4n+1} k^(k mod 4 - 2).
All terms are odd squares. (End)
LINKS
MAPLE
q:= 1: A[0]:= 1:
for i from 1 to 50 do
p:= A[i-1]*(4*i+1);
q:= q*(4*i-1);
g:= igcd(p, q);
A[i]:= p/g;
q:= q/g;
od:
seq(A[i]^2, i=0..50); # Robert Israel, Sep 09 2016
MATHEMATICA
Table[Denominator[Pochhammer[3/4, n]^2/Pochhammer[5/4, n]^2], {n, 0, 20}] (* Vaclav Kotesovec, Apr 06 2018 *)
CROSSREFS
Cf. A276239 (numerators).
Sequence in context: A030485 A036509 A034981 * A053919 A053927 A081195
KEYWORD
nonn,frac
AUTHOR
Artur Jasinski, Aug 25 2016
STATUS
approved

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Last modified March 29 08:51 EDT 2024. Contains 371268 sequences. (Running on oeis4.)