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Number of protruded partitions of n with largest part at most 2.
(Formerly M2463)
0

%I M2463 #12 Sep 05 2017 12:44:19

%S 1,3,5,10,17,31,53,92,156,265,445,746,1243,2066,3421,5652,9314,15320,

%T 25152,41232,67497,110361,180249,294115,479500,781143,1271675,2068987,

%U 3364358,5468074,8883329,14425997,23418648,38004865,61658326,100007327

%N Number of protruded partitions of n with largest part at most 2.

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%D R. P. Stanley, Ordered structures and partitions, Memoirs of the Amer. Math. Soc., no. 119 (1972).

%H R. P. Stanley, <a href="http://www.fq.math.ca/Scanned/13-3/stanley.pdf">A Fibonacci lattice</a>, Fib. Quart., 13 (1975), 215-232.

%F G.f.: (1-x)^2/Product(1-x-x^i+x^(1+2*i), i=1..2)-1. - _Emeric Deutsch_, Dec 19 2004

%p G:=(1-x)^2/Product(1-x-x^i+x^(1+2*i),i=1..2)-1: Gser:=series(G,x=0,39): seq(coeff(Gser,x^n),n=1..37); # _Emeric Deutsch_, Dec 19 2004

%K nonn

%O 1,2

%A _N. J. A. Sloane_.

%E More terms from _Emeric Deutsch_, Dec 19 2004