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A126561
Decimal expansion of (Pi^2-9)/12.
1
7, 2, 4, 6, 7, 0, 3, 3, 4, 2, 4, 1, 1, 3, 2, 1, 8, 2, 3, 6, 2, 0, 7, 5, 8, 3, 3, 2, 3, 0, 1, 2, 5, 9, 4, 6, 0, 9, 4, 7, 4, 9, 5, 0, 6, 0, 3, 3, 9, 9, 2, 1, 8, 8, 6, 7, 7, 7, 9, 1, 1, 4, 6, 8, 5, 0, 0, 3, 7, 3, 5, 2, 0, 1, 6, 0, 0, 4, 3, 6, 9, 1, 6, 8, 1, 4, 4, 5, 0, 3, 0, 9, 8, 7, 9, 3, 5, 2, 6, 5
OFFSET
-1,1
FORMULA
Equals Sum_{i>=1} 1/(i*(i+1)*(i+2)^2).
For n>1, a(n) = A072691(n+1).
EXAMPLE
0.072467033424113218236207583323...
MATHEMATICA
RealDigits[(Pi^2 - 9)/12, 10, 100][[1]] (* Amiram Eldar, May 17 2022 *)
PROG
(PARI) (Pi^2-9)/12 \\ Charles R Greathouse IV, Oct 01 2022
CROSSREFS
Cf. A072691.
Sequence in context: A154174 A257452 A021142 * A306858 A324558 A246508
KEYWORD
nonn,easy,cons
AUTHOR
Zak Seidov, Mar 12 2007
STATUS
approved