cp's OEIS Frontend

A371305 Triangle T(n,k) read by rows: number of chord diagrams with k isolated bracelets and a total of n chords.

%I A371305 #6 Jun 09 2024 23:58:30
%S A371305 1,2,1,5,2,1,17,8,2,1,79,27,8,2,1,554,128,31,8,2,1,5283,797,143,31,8,
%T A371305 2,1,65346,6939,878,148,31,8,2,1,966156,80025,7381,898,148,31,8,2,1,
%U A371305 16411700,1135841,83038,7494,904,148,31,8,2,1,312700297,18804319,1161866,83679,7519,904,148,31,8,2,1
%N A371305 Triangle T(n,k) read by rows: number of chord diagrams with k isolated bracelets and a total of n chords.
%C A371305 Multiset transformation of A054499.
%C A371305 The row sums 1, 3, 8, 28, 117, 724, 6265, 73353, 1054650, 17639167, ... are the Euler Transform of A054499.
%e A371305 T(3,2)=2: two bracelets with 3 chords in two variants (i) one bracelet with one chord and the other with 2 noncrossing chords, (ii) one bracelet with one chord and the other with 2 crossing chords.
%e A371305 1 ;
%e A371305 2 1 ;
%e A371305 5 2 1 ;
%e A371305 17 8 2 1 ;
%e A371305 79 27 8 2 1 ;
%e A371305 554 128 31 8 2 1 ;
%e A371305 5283 797 143 31 8 2 1 ;
%e A371305 65346 6939 878 148 31 8 2 1 ;
%e A371305 966156 80025 7381 898 148 31 8 2 1 ;
%e A371305 16411700 1135841 83038 7494 904 148 31 8 2 1 ;
%Y A371305 Cf. A054499.
%K A371305 nonn,tabl
%O A371305 1,2
%A A371305 _R. J. Mathar_, Mar 18 2024