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A127139 Inverse triangle of A126988, row sums = A023900. 3
1, -2, 1, -3, 0, 1, 0, -2, 0, 1, -5, 0, 0, 0, 1, 6, -3, -2, 0, 0, 1, -7, 0, 0, 0, 0, 0, 1, 0, 0, 0, -2, 0, 0, 0, 1, 0, 0, -3, 0, 0, 0, 0, 0, 1, 10, -5, 0, 0, -2, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row sums = A023900: (1, -1, -2, -1, -4, 2, -6, -1,...) Left column = A055615: (1, -2, -3, 0, -5, 6, -7,...) A127139 * [1, 2, 3,...] = [1, 0, 0, 0...] A127139 * [1, 0, 0, 0,...] = A055615 A127140 is the square of A127139.

LINKS

Table of n, a(n) for n=1..55.

FORMULA

Inverse triangle of A126988

EXAMPLE

First few rows of the triangle are:

1;

-2, 1;

-3, 0, 1;

0, -2, 0, 1;

-5, 0, 0, 0, 1;

6, -3, -2, 0, 0, 1;

-7, 0, 0, 0, 0, 0, 1;

...

MATHEMATICA

(*recurrence*) Clear[tt, t, nn, s]; nn = 10; s = 0; t[1, 1] = 1; t[n_, k_] := t[n, k] = If[k == 1, -Sum[t[n, k + i]/(i + 1)^(s - 1), {i, 1, n - 1}], If[Mod[n, k] == 0, t[n/k, 1], 0], 0]; Flatten[Table[Table[t[n, k], {k, 1, n}], {n, 1, nn}]] (* Mats Granvik, Mar 12 2016 *)

CROSSREFS

Cf. A126988, A055615, A023900, A127140.

Sequence in context: A323881 A062963 A143255 * A309103 A166139 A317367

Adjacent sequences:  A127136 A127137 A127138 * A127140 A127141 A127142

KEYWORD

tabl,sign

AUTHOR

Gary W. Adamson, Jan 06 2007

STATUS

approved

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Last modified January 25 16:42 EST 2020. Contains 331245 sequences. (Running on oeis4.)