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A372774
Decimal expansion of Sum_{k>=0} (-1)^k*(2*k + 1)!/(3*k + 1)!.
1
7, 7, 2, 4, 7, 7, 0, 5, 2, 2, 1, 3, 6, 9, 6, 3, 6, 4, 3, 5, 7, 8, 3, 6, 7, 0, 2, 4, 5, 5, 6, 0, 7, 2, 0, 5, 7, 9, 4, 6, 5, 8, 9, 0, 6, 9, 8, 4, 2, 8, 3, 3, 4, 7, 7, 9, 9, 0, 5, 4, 6, 8, 1, 1, 4, 2, 9, 2, 3, 0, 4, 0, 5, 6, 0, 4, 6, 6, 2, 7, 8, 5, 6, 0, 7, 1
OFFSET
0,1
FORMULA
HypergeometricPFQ((1,3/2),(2/3,4/3),-4/27).
EXAMPLE
0.772477052213696364357836702455607205794658...
MATHEMATICA
s = Sum[(-1)^k (2 k + 1)!/(3 k + 1)!, {k, 0, Infinity}]
d = N[s, 100]
First[RealDigits[d]]
N[HypergeometricPFQ[{1, 3/2}, {2/3, 4/3}, -(4/27)], 100]
PROG
(PARI) suminf(k=0, (-1)^k*(2*k + 1)!/(3*k + 1)!) \\ Michel Marcus, Jun 01 2024
CROSSREFS
Cf. A372773.
Sequence in context: A113810 A002161 A083871 * A255272 A335929 A303658
KEYWORD
cons,nonn
AUTHOR
Clark Kimberling, May 31 2024
STATUS
approved