%I #27 Dec 19 2015 09:59:22
%S 1,1,1,2,3,5,7,10,13,18,24,32,41,52,66,83,102,124,152,181,216,255,299,
%T 346,400,458,521,588,659,735,814,896,979,1067,1151,1239,1324,1407,
%U 1486,1564,1635,1700,1759,1809,1853,1887,1912,1925,1932,1925,1912,1887,1853
%N Number of n-node rooted identity trees of height at most 4.
%C A finite sequence with A038093(4) = 97 terms.
%H Alois P. Heinz, <a href="/A038083/b038083.txt">Table of n, a(n) for n = 1..97</a>
%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%H <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a>
%F Take Weigh transform of A038082 and shift right.
%p weigh:= proc(p) proc(n) `if`(n<0,1, coeff(mul((1+x^k)^p(k), k=1..n), x,n)) end end: wsh:= p-> n-> weigh(p)(n-1): a:= wsh(n-> `if`(n>0 and n<12, [1$3,2$5,1$3][n],0)): seq(a(n), n=1..97); # _Alois P. Heinz_, Sep 10 2008
%t a = Drop[CoefficientList[ Series[x (1 + x) (1 + x^2) (1 + x^3) (1 + x^4), {x, 0, 11}], x], 1]; nn = 97; Drop[ CoefficientList[ Series[x Product[(1 + x^i)^a[[i]], {i, 1, 11}], {x, 0, nn}], x], 1] (* _Geoffrey Critzer_, Aug 01 2013 *)
%Y Cf. A038081-A038093.
%K nonn,fini,full
%O 1,4
%A _Christian G. Bower_, Jan 04 1999
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