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A218580 Triangle read by rows: T(n,k) is the number of ascent sequences of length n with first occurrence of the maximal value at position k-1.

%I A218580 #8 Nov 09 2012 16:06:57
%S A218580 1,1,1,1,2,2,1,4,5,5,1,8,13,15,16,1,16,35,47,56,62,1,32,97,153,204,
%T A218580 248,279,1,64,275,515,770,1030,1257,1423,1,128,793,1785,3000,4424,
%U A218580 5869,7140,8100,1,256,2315,6347,12026,19582,28293,37058,44843,50887
%N A218580 Triangle read by rows: T(n,k) is the number of ascent sequences of length n with first occurrence of the maximal value at position k-1.
%C A218580 Row sums are A022493.
%C A218580 Second column are powers of 2.
%e A218580 Triangle starts:
%e A218580 [ 1]  1,
%e A218580 [ 2]  1, 1,
%e A218580 [ 3]  1, 2, 2,
%e A218580 [ 4]  1, 4, 5, 5,
%e A218580 [ 5]  1, 8, 13, 15, 16,
%e A218580 [ 6]  1, 16, 35, 47, 56, 62,
%e A218580 [ 7]  1, 32, 97, 153, 204, 248, 279,
%e A218580 [ 8]  1, 64, 275, 515, 770, 1030, 1257, 1423,
%e A218580 [ 9]  1, 128, 793, 1785, 3000, 4424, 5869, 7140, 8100,
%e A218580 [10]  1, 256, 2315, 6347, 12026, 19582, 28293, 37058, 44843, 50887,
%e A218580 ...
%Y A218580 Cf. A022493 (number of ascent sequences).
%Y A218580 Cf. A218579 (ascent sequences with last zero at position k-1), A218581 (ascent sequences with last occurrence of the maximal value at position k-1).
%Y A218580 Cf. A137251 (ascent sequences with k ascents), A218577 (ascent sequences with maximal element k), A175579 (ascent sequences with k zeros).
%K A218580 nonn,tabl
%O A218580 1,5
%A A218580 _Joerg Arndt_, Nov 03 2012