This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A144297 #15 Sep 28 2023 14:24:08 %S A144297 1,3,12,65,465,4212,46441,604389,9071250,154267865,2931801639, %T A144297 61578273462,1416474723373,35415138314415,956276678789100, %U A144297 27733572777976973,859779201497486829,28373745267763162716,993110842735800666085,36746019445535955976665 %N A144297 BINOMIAL transform of A001515. %H A144297 Vincenzo Librandi, <a href="/A144297/b144297.txt">Table of n, a(n) for n = 0..200</a> %H A144297 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a> %F A144297 From _Vaclav Kotesovec_, Oct 20 2012: (Start) %F A144297 E.g.f.: exp(1+x-sqrt(1-2*x))/sqrt(1-2*x). %F A144297 Recurrence: a(n) = (2*n+1)*a(n-1) - (4*n-5)*a(n-2) + 2*(n-2)*a(n-3). %F A144297 a(n) ~ 2^(n+1/2)*n^n/exp(n-3/2). (End) %F A144297 a(n) = Sum_{j=0..n} binomial(n,j)*A001515(j). - _G. C. Greubel_, Sep 28 2023 %t A144297 CoefficientList[Series[E^(1+x-Sqrt[1-2*x])/Sqrt[1-2*x],{x,0,20}],x]*Range[0, 20]! (* _Vaclav Kotesovec_, Oct 20 2012 *) %o A144297 (Magma) I:=[1,3,12]; [n le 3 select I[n] else (2*n-1)*Self(n-1) -(4*n-9)*Self(n-2) +2*(n-3)*Self(n-3): n in [1..30]]; // _G. C. Greubel_, Sep 28 2023 %o A144297 (SageMath) %o A144297 def A144297_list(prec): %o A144297 P.<x> = PowerSeriesRing(QQ, prec) %o A144297 return P( exp(1+x-sqrt(1-2*x))/sqrt(1-2*x) ).egf_to_ogf().list() %o A144297 A144297_list(40) # _G. C. Greubel_, Sep 28 2023 %Y A144297 Cf. A001515. %K A144297 nonn %O A144297 0,2 %A A144297 _N. J. A. Sloane_, Dec 04 2008