cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A127742 Triangle read by rows with shape A000041 which refines the Catalan triangle A033184 using sequence A048996.

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%I A127742 #7 Jan 14 2013 21:48:21
%S A127742 1,1,1,2,2,1,5,4,1,3,1,14,10,4,6,3,4,1,42,28,10,4,15,12,1,8,6,5,1,132,
%T A127742 84,28,20,42,30,12,6,20,24,4,10,10,6,1,429,264,84,56,25,126,84,60,15,
%U A127742 12,56,60,24,24,1,25,40,10,12,15,7,1,1430,858,264,168,140,396,252,168,75
%N A127742 Triangle read by rows with shape A000041 which refines the Catalan triangle A033184 using sequence A048996.
%C A127742 Contribution from _R. J. Mathar_, Jul 16 2010: (Start)
%C A127742 The entries count Dyck paths of length 2n which have a step/stride pattern between consecutive returns to the horizontal axes (after sorting) equivalent to the k-th partition of n.
%C A127742 Equivalent means that each distance between two x (where y=0) is divided by 2 prior to comparison.
%C A127742 Example: if the x-values are (0,4,8,10,16) with 2n=16, the strides are 4,4,2,6, equal to 2,2,1,3 after division by 2, and contribute to the 1^1,2^2,3^1 partition T(8,14). (End)
%e A127742 The triangle begins
%e A127742 1
%e A127742 1 1
%e A127742 2 2 1
%e A127742 5 4 1 3 1
%e A127742 14 10 4 6 3 4 1
%e A127742 etc
%K A127742 nonn,tabf
%O A127742 1,4
%A A127742 _Alford Arnold_, Feb 23 2007
%E A127742 More terms from _R. J. Mathar_, Jul 16 2010