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A287704 Triangle read by rows, denominators of T(n,k) = (-1)^(n+k)*binomial(n-1,k)* Bernoulli(n+k)/ (n+k) for n>=1, 0<=k<=n-1. 1
2, 12, 1, 1, 60, 1, 120, 1, 84, 1, 1, 63, 1, 60, 1, 252, 1, 24, 1, 132, 1, 1, 40, 1, 33, 1, 5460, 1, 240, 1, 44, 1, 936, 1, 12, 1, 1, 33, 1, 585, 1, 3, 1, 1020, 1, 132, 1, 910, 1, 2, 1, 680, 1, 1596, 1, 1, 3276, 1, 1, 1, 680, 1, 1197, 1, 660, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..66.

EXAMPLE

1:   2

2:  12,  1

3:   1, 60, 1

4: 120,  1, 84,   1

5:   1, 63,  1,  60,   1

6: 252,  1, 24,   1, 132,    1

7:   1, 40,  1,  33,   1, 5460,  1

8: 240,  1, 44,   1, 936,    1, 12,    1

9:   1, 33,  1, 585,   1,    3,  1, 1020, 1

MAPLE

T := (n, k) -> denom((-1)^(n+k)*binomial(n-1, k)*bernoulli(n+k)/(n+k)):

for n from 1 to 9 do seq(T(n, k), k=0..n-1) od;

MATHEMATICA

T[n_, k_]:=Denominator[(-1)^n*Binomial[n - 1, k] BernoulliB[k + n]/(k + n)]; Table[T[n, k], {n, 11}, {k, 0, n - 1}]//Flatten (* Indranil Ghosh, Jul 27 2017 *)

PROG

(PARI) T(n, k) = denominator((-1)^n*binomial(n-1, k)*bernfrac(k+n)/(k+n));

tabl(nn) = for (n=1, nn, for (k=0, n-1, print1(T(n, k), ", ")); print); \\ Michel Marcus, Jul 28 2017

CROSSREFS

Numerators in A287703.

Sequence in context: A166489 A160367 A016736 * A082185 A113491 A107773

Adjacent sequences:  A287701 A287702 A287703 * A287705 A287706 A287707

KEYWORD

nonn,tabl,frac

AUTHOR

Peter Luschny, Jun 21 2017

STATUS

approved

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Last modified August 5 03:00 EDT 2021. Contains 346457 sequences. (Running on oeis4.)