A396929 Decimal expansion of the sum of the reciprocals of square pyramidal factorials A135438.

2, 2, 1, 4, 7, 7, 0, 6, 5, 8, 5, 9, 6, 4, 5, 0, 6, 2, 7, 8, 8, 2, 3, 9, 5, 5, 2, 8, 6, 2, 3, 2, 5, 1, 9, 7, 7, 7, 6, 5, 9, 7, 2, 0, 0, 5, 8, 5, 3, 6, 3, 6, 3, 7, 1, 1, 3, 1, 2, 6, 0, 5, 6, 9, 1, 2, 9, 3, 6, 8, 2, 4, 2, 4, 4, 5, 9, 0, 6, 7, 6, 6, 4, 4, 8, 9, 7, 6, 4, 7, 2, 4, 9, 7, 7, 3, 6, 5, 3, 6, 9, 7, 5, 1, 8, 7, 1, 2, 3, 9, 4

Offset

1,1

Links

Kelvin Voskuijl, Table of n, a(n) for n = 1..10000

Formula

Equals hypergeom([], [3/2, 2], 3).

Example

2.21477065859645...

Mathematica

RealDigits[HypergeometricPFQ[{}, {3/2, 2}, 3], 10, 120][[1]]

Prog

(PARI) suminf(n=0, 1/((n+1)!*(2*n+1)!/12^n))

Crossrefs

Cf. A135438.

Cf. A001113, A070910, A271574, A396449, A396450, A396451, A396929, A396930, A396931, A396932, A396933.

Sequence in context: A096747 A299504 A300979 * A371889 A386621 A167622

Adjacent sequences: A396926 A396927 A396928 * A396930 A396931 A396932

Keyword

nonn,cons

Author

Kelvin Voskuijl, Jun 11 2026

Status

approved