A281231 Exponential transform of the tetrahedral numbers (A000292).
1, 1, 5, 23, 133, 916, 7107, 61286, 580505, 5968400, 66032901, 780962524, 9817927385, 130572957724, 1829676460991, 26919714974436, 414591408939313, 6665930432840304, 111624874150941193, 1942675652654112012, 35071252458352443001, 655641049733709757516
Offset: 0
Keywords
Examples
E.g.f.: A(x) = 1 + x/1! + 5*x^2/2! + 23*x^3/3! + 133*x^4/4! + 916*x^5/5! + 7107*x^6/6! + ...
Links
- M. Bernstein and N. J. A. Sloane, Some canonical sequences of integers, Linear Alg. Applications, 226-228 (1995), 57-72; erratum 320 (2000), 210. [Link to arXiv version]
- M. Bernstein and N. J. A. Sloane, Some canonical sequences of integers, Linear Alg. Applications, 226-228 (1995), 57-72; erratum 320 (2000), 210. [Link to Lin. Alg. Applic. version together with omitted figures]
- N. J. A. Sloane, Transforms
- Eric Weisstein's World of Mathematics, Exponential Transform
- Eric Weisstein's World of Mathematics, Tetrahedral Number
- Index to sequences related to pyramidal numbers
Programs
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Maple
a:= proc(n) option remember; `if`(n=0, 1, add(a(n-j) *binomial(n-1, j-1)*j*(j+1)*(j+2)/6, j=1..n)) end: seq(a(n), n=0..25); # Alois P. Heinz, Jan 18 2017
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Mathematica
Range[0, 21]! CoefficientList[Series[Exp[Exp[x] x (1 + x + x^2/6)], {x, 0, 21}], x]
Formula
E.g.f.: exp(exp(x)*x*(1+x+x^2/6)).