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A108744
Decimal expansion of B = Sum_{ n > 0 } 1/A007559(n).
3
1, 2, 8, 9, 5, 7, 8, 5, 5, 6, 3, 7, 2, 7, 4, 1, 0, 4, 7, 1, 2, 0, 0, 4, 8, 0, 0, 0, 4, 4, 6, 1, 5, 0, 6, 7, 7, 7, 4, 2, 8, 0, 4, 0, 5, 7, 4, 3, 7, 0, 0, 5, 2, 5, 9, 6, 0, 7, 6, 6, 4, 1, 9, 6, 8, 0, 1, 6, 3, 7, 8, 9, 2, 4, 4, 3, 6, 1, 0, 3, 5, 8, 3, 9, 8, 6, 7, 4, 5, 9, 0, 3, 8, 3, 8, 4, 3, 0, 0, 9, 3, 4, 8, 7, 8
OFFSET
1,2
FORMULA
A = B + C with A = Gamma(1/3)*(e/9)^(1/3) and C = 1/(1+2/(1+3/(1+5/(1+6/(1+8/(1+9/(1+11/(1+. .)))))))).
EXAMPLE
1.28957855637...
MATHEMATICA
E^(1/3)*(Gamma[1/3] - Gamma[1/3, 1/3])/3^(2/3) // RealDigits[#, 10, 105]& // First (* Jean-François Alcover, Feb 22 2013 *)
PROG
(PARI) B=sum(n=1, 100, 1./prod(k=0, n-1, 3*k+1)) /* Paul D. Hanna */
CROSSREFS
Sequence in context: A140241 A340536 A340778 * A195724 A081819 A296850
KEYWORD
nonn,cons
AUTHOR
Philippe Deléham, Jun 22 2005
EXTENSIONS
More terms from Paul D. Hanna, Jun 25 2005
STATUS
approved