The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

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