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A101630
Denominator of partial sums of a certain series.
1
1, 42, 6006, 204204, 3879876, 446185740, 38818159380, 2406725881560, 89048857617720, 3651003162326520, 156993135980040360, 51650741737433278440, 2737489312083963757320, 2737489312083963757320
OFFSET
1,2
COMMENTS
The numerators are given in A101629.
a(13) and a(14) are indeed identical, namely 2737489312083963757320.
FORMULA
a(n)=denominator(s(n)) with s(n)=15*sum(1/((4*k-1)*k*(4*k+1)), k=1..n).
CROSSREFS
Sequence in context: A268546 A102967 A091545 * A273628 A005791 A167668
KEYWORD
nonn,frac,easy
AUTHOR
Wolfdieter Lang, Dec 23 2004
STATUS
approved