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A257372 a(n) = denominators of A255935(n) * triangle T(n,k) for Bernoulli(k+2), k=0 to n-1. 0
1, 6, 6, 15, 30, 21, 42, 15, 30, 33, 66, 1365, 2730, 3, 6, 255, 510, 399, 798, 165, 330, 69, 138, 1365, 2730, 3, 6, 435, 870, 7161, 14322, 255, 510, 3, 6, 959595, 1919190, 3, 6, 6765, 13530, 903, 1806, 345, 690 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Generally, A255935(n) multiplied by triangle T(n,k) for s(k), k=0 to n-1 yields an autosequence of the first kind (a sequence whose main diagonal is 0's).

Here s(k) = 1/6, 0, -1/30, ... from A164555(n+2)/A027642(n+2). Hence

0                              =  0/1

1/6, 0                         =  1/6

1/6, 0,     0                  =  1/6

1/6, 0, -1/10, 0               = 1/15

1/6, 0,  -1/5, 0, 0            =-1/30

... .

a(n) are the row sums denominators.

Compare to A051716(n+2)/A051717(n+2).

Hence the difference table

0,       1/6,      1/6,  1/15, -1/30, -1/21, 1/42, ...

1/6,       0,    -1/10, -1/10, -1/70,  1/14, ...

-1/6,  -1/10,        0,  3/35,  3/35, ...

1/15,   1/10,     3/35,     0, ...

1/30,  -1/70,    -3/35, ...

-1/21, -1/14, ...

-1/42, ...

... .

LINKS

Table of n, a(n) for n=0..44.

FORMULA

a(2n) = A002445(n).

a(2n+3) = A001897(n+2).

a(2n+2) = A040000(n) * a(2n+1).

CROSSREFS

Cf. A255935, A027641/A027642, A164555/A027642, A001897, A002445, A040000, A051716/A051717.

Sequence in context: A266223 A256675 A290931 * A058563 A175561 A341202

Adjacent sequences:  A257369 A257370 A257371 * A257373 A257374 A257375

KEYWORD

nonn

AUTHOR

Paul Curtz, Apr 21 2015

STATUS

approved

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Last modified June 18 01:16 EDT 2021. Contains 345098 sequences. (Running on oeis4.)