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A025538 a(n) = (1/s(1) - 1/s(2) + ... + d/s(n+1)) * LCM{1, 2, ..., n}, where d = (-1)^n, s = A002944, i.e., s(k) = LCM of row k of Pascal's triangle. 0
1, 0, 1, 1, 3, 9, 10, 66, 135, 395, 396, 4344, 4345, 56471, 56486, 56478, 112957, 1920251, 1920252, 36484768, 36484789, 36484767, 36484768, 839149640, 839149645, 4195748199, 4195748208, 12587244596, 12587244597, 365030093283, 365030093284 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..30.

FORMULA

a(n) = A003418(n) * Sum_{k=1..n+1} (-1)^(k+1)/A002944(k). - Sean A. Irvine, Sep 04 2019

CROSSREFS

Sequence in context: A335029 A228450 A121057 * A070354 A174565 A074261

Adjacent sequences:  A025535 A025536 A025537 * A025539 A025540 A025541

KEYWORD

nonn

AUTHOR

Clark Kimberling

EXTENSIONS

Title improved by Sean A. Irvine, Sep 04 2019

STATUS

approved

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Last modified June 5 16:19 EDT 2020. Contains 334852 sequences. (Running on oeis4.)