A353911 - OEIS

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A353911

Product_{n>=1} 1 / (1 - a(n)*x^n/n!) = 1 + tan(x).

1, -2, 2, -32, 56, -416, 3184, -85504, 309760, -4087552, 48104704, -546922496, 10591523840, -194387924992, 3133776259072, -129880886411264, 1249919350046720, -29073986250604544, 624022403933077504, -15137719350365519872, 381632216575339397120, -11149155036737662615552

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..22.

MATHEMATICA

nn = 22; f[x_] := Product[1/(1 - a[n] x^n/n!), {n, 1, nn}]; sol = SolveAlways[0 == Series[f[x] - 1 - Tan[x], {x, 0, nn}], x]; Table[a[n], {n, 1, nn}] /. sol // Flatten

CROSSREFS

Cf. A000182, A009006, A353583, A353584, A353611, A353873, A353910, A353912.

Sequence in context: A371562 A309191 A372305 * A303568 A353928 A121788

Adjacent sequences: A353908 A353909 A353910 * A353912 A353913 A353914

KEYWORD

sign

AUTHOR

Ilya Gutkovskiy, May 10 2022

STATUS

approved