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A180403 Numerator in Moebius transform of A001790/A046161. 4
1, -1, -5, -3, -93, 95, -793, -211, -5853, 27003, -215955, 57459, -3518265, 3602027, 16811055, -4362627, -1846943453, 293601363, -14911085359, 4487888279, 144251733709, 245294787521, -1936010885087, 228009405371, -11179552565305, 63485965327535, -48562641580527 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Consider a lower triangular matrix T(n,k) defined by T(n,1)=A001790/A046161, k>1: T(n,k) = (Sum_{i=1..k-1} T(n-i,k-1)) - (Sum_{i=1..k-1} T(n-i,k)). The first column in the matrix inverse of T(n,k) will have the fraction A180403/A046161 in its first column.
The sequence considers the Moebius transform 1, -1/2, -5/8, -3/16, -93/128, ... of the sequence A001790(n-1)/A046161(n-1), i.e., assigning offset 1 to A001790 and A046161. - R. J. Mathar, Apr 22 2011
LINKS
FORMULA
Lambert series: Sum_{n >= 1} (A180403(n)/A046161(n))*x^n/(1-x^n) = x/sqrt(1-x). - Mats Granvik, Sep 07 2010
CROSSREFS
Cf. A001790, A046161 (denominators).
Sequence in context: A370551 A350213 A255599 * A343582 A267512 A230389
KEYWORD
frac,sign
AUTHOR
Mats Granvik, Sep 02 2010
EXTENSIONS
Signs of terms corrected by Mats Granvik, Sep 05 2010
Corrected and edited by Mats Granvik, Oct 08 2010
STATUS
approved

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Last modified March 29 11:45 EDT 2024. Contains 371278 sequences. (Running on oeis4.)