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%I #18 May 03 2019 03:04:47
%S 0,1,4,30,304,3885,59976,1085973,22571200,529712667,13856212600,
%T 399773871068,12612288989664,431948624278795,15960564546516240,
%U 632898895109081310,26809122466181751552,1208177444352064438155,57719104861915100554200,2913802658820378870546498,154991214138728849712151200
%N a(n) = n! * [x^n] exp(n*x)*BesselI(1,2*x).
%C The n-th term of the n-th binomial transform of A138364.
%H Seiichi Manyama, <a href="/A292629/b292629.txt">Table of n, a(n) for n = 0..386</a>
%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%F a(n) = A292628(n,n).
%F a(n) ~ BesselI(1,2) * n^n. - _Vaclav Kotesovec_, Sep 20 2017
%F a(n) = [x^(n-1)] (1+n*x+x^2)^n = [x^(n+1)] (1+n*x+x^2)^n. - _Seiichi Manyama_, May 01 2019
%t Table[n!*SeriesCoefficient[E^(n*x)*BesselI[1,2*x],{x,0,n}], {n,0,20}] (* _Vaclav Kotesovec_, Sep 20 2017 *)
%o (PARI) a(n) = polcoef((1+n*x+x^2)^n, n-1); \\ _Michel Marcus_, May 01 2019
%Y Main diagonal of A292628.
%Y Cf. A138364, A186925.
%K nonn
%O 0,3
%A _Ilya Gutkovskiy_, Sep 20 2017