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%I #17 May 10 2023 08:22:32
%S 1,2,4,9,22,59,170,525,1716,5917,21362,80533,315516,1281913,5383622,
%T 23330405,104084736,477371217,2246811730,10839493637,53528916508,
%U 270318789249,1394426035918,7341439399397,39413238225512,215607783811041
%N Row sums of number triangle A070895.
%H G. C. Greubel, <a href="/A187044/b187044.txt">Table of n, a(n) for n = 0..795</a>
%F E.g.f.: exp(x+x^2/2)*(sqrt(pi/2)*ERF(x/sqrt(2)) + 1).
%F Conjecture: a(n) -2*a(n-1) +(2-n)*a(n-2) +(n-2)*a(n-3)=0. - _R. J. Mathar_, Sep 29 2012
%F a(n) ~ (sqrt(2)+sqrt(Pi))/2 * exp(sqrt(n)-n/2-1/4)*n^(n/2) * (1+7/(24*sqrt(n))). - _Vaclav Kotesovec_, Aug 15 2013
%F a(n) = A193361(n+2). - _Vaclav Kotesovec_, Feb 14 2014
%t CoefficientList[Series[E^(x+x^2/2)*(Sqrt[Pi/2]*Erf[x/Sqrt[2]]+1), {x, 0, 20}], x]* Range[0, 20]! (* _Vaclav Kotesovec_, Aug 15 2013 *)
%Y Cf. A070895, A193361.
%K nonn,easy
%O 0,2
%A _Paul Barry_, Mar 02 2011
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