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!)
 A273197 a(n) = denominator of T(n, 2) with T(n, m) = Sum_{k=0..n}( 1/(m*k+1) * Sum_{j=0..m*k} (-1)^j*C(k,j)*j^(m*n) ). 2
 1, 3, 15, 105, 15, 1155, 455, 15, 19635, 95095, 2145, 31395, 7735, 2805, 10818885, 50115065, 3315, 596505, 80925845, 3795, 18515805, 221847535, 2211105, 204920500785, 1453336885, 148335, 95055765, 287558635, 27897511785, 397299047145, 5613813089885, 8897205 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS T(n,0) are the natural numbers, T(n,1) the Bernoulli numbers. LINKS MATHEMATICA Table[Function[{n, m}, If[n == 0, 1, Denominator@ Sum[1/(m k + 1) Sum[(-1)^j Binomial[k, j] j^(m n), {j, 0, m k}], {k, 0, n}]]][n, 2], {n, 0, 31}] (* Michael De Vlieger, Jun 26 2016 *) PROG (Sage) def T(n, m): return sum(1/(m*k+1)*sum((-1)^j*binomial(k, j)*j^(m*n) for j in (0..m*k)) for k in (0..n)) def a(n): return T(n, 2).denominator() print([a(n) for n in (0..31)]) CROSSREFS Cf. A273196 (numerators). T(n,0) = A000027(n) for n>=1. T(n,1) = A027641(n)/A027642(n) for all n>=0. T(n,1)*(1*n+1)! = A129814(n) for all n>=0. T(n,2)*(2*n+1)! = A273198(n) for all n>=0. Sequence in context: A003276 A136092 A338724 * A255427 A181131 A293996 Adjacent sequences:  A273194 A273195 A273196 * A273198 A273199 A273200 KEYWORD nonn,frac AUTHOR Peter Luschny, Jun 26 2016 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 July 28 14:19 EDT 2021. Contains 346335 sequences. (Running on oeis4.)