A368369 AGM transform of odd numbers.

0, 4, 324, 38656, 6812500, 1691793216, 566933589544, 247467140448256, 136744348012840296, 93452709250000000000, 77479910616937022101996, 76677271817228569527975936, 89338843947334074736463717884, 121104748419604219251183463776256, 189040371972603446582336425781250000, 336742459165125951045187297509382291456

Offset

1,2

Comments

See A368366 for further information.

Links

Paolo Xausa, Table of n, a(n) for n = 1..210

Mathematica

A368369[n_] := With[{m = n^n}, m*(m-(2*n-1)!!)];
Array[A368369, 20] (* Paolo Xausa, Jan 29 2024 *)

Prog

(PARI) a368369(n) = {my(v=vector(n, i, i+i-1)); vecsum(v)^n - n^n*vecprod(v)}; \\ Hugo Pfoertner, Jan 24 2024
(Python)
from sympy import factorial2
def A368369(n): return (m:=n**n)*(m-factorial2((n<<1)-1)) # Chai Wah Wu, Jan 25 2024

Crossrefs

Cf. A005408, A368366.

Sequence in context: A186163 A159492 A368619 * A053917 A005832 A195501

Adjacent sequences: A368366 A368367 A368368 * A368370 A368371 A368372

Keyword

nonn

Author

N. J. A. Sloane, Jan 24 2024

Status

approved