login
(k-1)/2 where k runs over odd terms of A001372.
1

%I #8 Oct 21 2017 09:45:10

%S 0,0,1,3,9,23,171,475,1307,10245,28951,233099,664496,5442024,

%T 3109434694,218785948496

%N (k-1)/2 where k runs over odd terms of A001372.

%C Original definition: Suggested by A001372 as odd numbers to 130.

%H F. Hivert, J.-C. Novelli and J.-Y. Thibon, <a href="https://arxiv.org/abs/math/0605262">Commutative combinatorial Hopf algebras</a>, arXiv:math/0605262 [math.CO], 2006.

%F A129834 = { (A001372(n)-1)/2 ; n such that A001372(n) is odd }. - Corrected by _M. F. Hasler_, Nov 05 2014

%t A001372 = {1, 1, 3, 7, 19, 47, 130, 343, 951, 2615, 7318, 20491, 57903, 163898, 466199, 1328993, 3799624, 10884049, 31241170, 89814958, 258604642, 745568756, 2152118306, 6218869389, 17988233052, 52078309200, 150899223268, 437571896993 }; Flatten[Table[If[IntegerQ[(A001372[[n]] - 1)/2], (A001372[[n]] - 1)/2, {}], { n, 1.Length[A001372]}]]

%Y Cf. A001372.

%K nonn,less

%O 1,4

%A _Roger L. Bagula_, May 21 2007

%E New definition and minor edits by _M. F. Hasler_, Nov 05 2014