cp's OEIS Frontend

A119469 Triangle read by rows: row n gives coefficients (lowest degree first) of P_n(x), where P_0(x) = P_1(x) = 1; P_n(x) = P_{n-1}(x) + x^(n-2)*P_{n-2}(x).

%I A119469 #8 Jan 01 2017 02:03:32
%S A119469 1,1,2,2,1,2,1,2,2,1,2,2,1,2,1,2,2,3,1,2,2,1,2,2,3,3,3,2,2,1,2,1,2,2,
%T A119469 3,3,5,3,4,3,3,1,2,2,1,2,2,3,3,5,5,5,5,5,4,5,3,2,2,1,2,1,2,2,3,3,5,5,
%U A119469 7,6,7,6,8,6,7,5,5,3,3,1,2,2,1,2,2,3,3,5,5,7,8,8,8,10,9,10,10,10,8
%N A119469 Triangle read by rows: row n gives coefficients (lowest degree first) of P_n(x), where P_0(x) = P_1(x) = 1; P_n(x) = P_{n-1}(x) + x^(n-2)*P_{n-2}(x).
%C A119469 P_n(x) has degree A002620(n).
%H A119469 Seiichi Manyama, <a href="/A119469/b119469.txt">Table of n, a(n) for n = 0..9549 (rows n=0..49 of triangle, flattened).</a>
%e A119469 Triangle begins:
%e A119469 1
%e A119469 1
%e A119469 2
%e A119469 2,1
%e A119469 2,1,2
%e A119469 2,1,2,2,1
%e A119469 2,1,2,2,3,1,2
%e A119469 2,1,2,2,3,3,3,2,2,1
%e A119469 2,1,2,2,3,3,5,3,4,3,3,1,2
%e A119469 2,1,2,2,3,3,5,5,5,5,5,4,5,3,2,2,1
%p A119469 P[0]:=1; P[1]:=1; d:=[0,0]; M:=14; for n from 2 to M do P[n]:=expand(P[n-1]+q^(n-2)*P[n-2]);
%p A119469 lprint(seriestolist(series(P[n],q,M^2))); d:=[op(d),degree(P[n],q)]; od: d;
%Y A119469 A variant of A127836.
%Y A119469 Rows converge to A003113.
%K A119469 nonn,tabf
%O A119469 0,3
%A A119469 _N. J. A. Sloane_, Apr 10 2007