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 A091605 Column 2 of triangle A091602. 2

%I

%S 1,0,2,2,3,4,7,8,12,15,21,26,35,43,57,70,89,109,138,167,208,251,309,

%T 371,452,539,652,775,929,1099,1311,1543,1829,2146,2529,2957,3469,4040,

%U 4721,5481,6377,7381,8559,9875,11412,13133,15128,17364,19945,22833

%N Column 2 of triangle A091602.

%H Alois P. Heinz, <a href="/A091605/b091605.txt">Table of n, a(n) for n = 2..1000</a>

%F a(n) = A000726(n) - A000009(n).

%e a(7) counts these partitions: 511, 331, 322, 3211. - _Clark Kimberling_, Mar 10 2014

%t d[n_] := Select[IntegerPartitions[n], Max[Length /@ Split@#] == 2 &];

%t t = Table[d[n], {n, 12}] (* shows partitions *)

%t u = Table[Length[d[n]], {n, 2, 30}] (* counts partitions *)

%t (* _Clark Kimberling_, Mar 10 2014 *)

%K nonn

%O 2,3

%A _Christian G. Bower_, Jan 23 2004

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Last modified December 8 20:37 EST 2021. Contains 349596 sequences. (Running on oeis4.)