A370556 - OEIS

A370556

a(n) is the denominator of f(n)*conj(f(n)), where f(n) = Product_{k=1..n} (1/k + i), i is the imaginary unit, and conj(z) is the complex conjugate of z.

%I #7 Feb 23 2024 07:10:20

%S 1,2,9,144,72,2592,63504,4064256,164602368,658409472,39833773056,

%T 5736063320064,2868031660032,562134205366272,2529603924148224,

%U 647578604581945344,323789302290972672,104907733942275145728,18935845976580663803904,302973535625290620862464,66805664605376581900173312

%N a(n) is the denominator of f(n)*conj(f(n)), where f(n) = Product_{k=1..n} (1/k + i), i is the imaginary unit, and conj(z) is the complex conjugate of z.

%o (PARI) a370556(n) = my (f(n)=prod(k=1, n, 1/k + I)); denominator(f(n)*conj(f(n)))

%Y A370555 are the corresponding numerators.

%Y Cf. A370547, A370548, A370549, A370550, A370551, A370552, A370553, A370554.

%K nonn,frac,easy

%O 1,2

%A _Hugo Pfoertner_, Feb 23 2024