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A392026
Decimal expansion of 113*Pi + 355.
0
7, 0, 9, 9, 9, 9, 9, 6, 9, 8, 5, 5, 6, 4, 6, 6, 3, 5, 9, 4, 6, 2, 7, 8, 7, 0, 2, 3, 1, 0, 5, 8, 3, 8, 2, 5, 9, 1, 4, 2, 8, 0, 1, 4, 2, 1, 2, 9, 3, 8, 6, 9, 5, 7, 7, 7, 0, 1, 6, 8, 7, 3, 8, 9, 3, 0, 7, 8, 3, 2, 5, 3, 9, 1, 0, 3, 4, 1, 6, 1, 6, 8, 4, 4, 9, 6, 7, 9, 3, 5, 2, 6, 3, 6, 5, 9, 2, 2, 8, 6, 8, 1, 9, 8, 2, 7, 3, 3, 7, 7
OFFSET
3,1
COMMENTS
For a given exponent k, Sum_{m>=1} m^k*2^m/binomial(2*m,m) = (r/2)*Pi + s where r = A014307(k+1) and s = A180875(k), and the present constant is k=4, and r/(2*s) ~ Pi.
LINKS
D. H. Lehmer, Interesting Series Involving the Central Binomial Coefficient, The American Mathematical Monthly, 92:7 (1985), 449-457.
FORMULA
Equals Sum_{m>=1} m^4*2^m/binomial(2*m, m).
Equals HypergeometricPFQ({2, 2, 2, 2, 2}, {1, 1, 1, 3/2}, 1/2).
Equals 710 - 113 * A226043. - Amiram Eldar, Dec 27 2025
EXAMPLE
709.9999698556466359462787...
MATHEMATICA
RealDigits[113 Pi + 355, 10, 110][[1]]
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Artur Jasinski, Dec 27 2025
STATUS
approved