%I A123028
%S A123028 1,1,19,37,1159,3367,147193,569023,31940881,154205233,10572431611,
%T A123028 61219477501,4958470425559,33487054193047,3128794838527729,
%U A123028 24144166073186887,2556225383077154593,22188488621258749153
%N A123028 A003215 inside a second linear differential equation recursion: b(n)=2*b(n-1)-b(n-2)+6-->
               1+3*n+3*n^2 a(n)=b(n)*a[n-2]/(n*(n-1)).
%F A123028 b(n)=2*b(n-1)-b(n-2)+6-->1+3*n+3*n^2 a(n)=b(n)*a[n-2]/(n*(n-1)) Output=a(n)*n!
%t A123028 f[n_Integer] = Module[{a}, a[n] /. RSolve[{a[n] == 2*a[n - 1] - a[n - 
               2] + 6, a[0] == 1, a[1] == 7}, a[n], n][[1]] // FullSimplify] ; Clear[a] 
               a[n_] := a[n] = f[n]*a[n - 2]/(n*(n - 1)); a[0] = 1; a[1] = 1; Table[ExpandAll[a[n]*n! 
               ], {n, 0, 30}]
%Y A123028 Cf. A003215.
%Y A123028 Sequence in context: A136063 A111441 A144594 this_sequence A067205 A040342 
               A164009
%Y A123028 Adjacent sequences: A123025 A123026 A123027 this_sequence A123029 A123030 
               A123031
%K A123028 nonn,uned
%O A123028 1,3
%A A123028 Roger Bagula (rlbagulatftn(AT)yahoo.com), Sep 25 2006