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.
%I A357583 #10 Apr 06 2025 14:53:35 %S A357583 1,0,1,0,2,1,0,5,4,1,0,15,14,6,1,0,52,50,27,8,1,0,203,189,113,44,10,1, %T A357583 0,877,764,471,212,65,12,1,0,4140,3311,2013,974,355,90,14,1,0,21147, %U A357583 15378,8951,4440,1790,550,119,16,1,0,115975,76418,41745,20526,8727,3027,805,152,18,1 %N A357583 Triangle read by rows. Convolution triangle of the Bell numbers. %F A357583 Conjecture: row polynomials are x*R(n,1) for n > 0 where R(n,k) = R(n-1,k+1) + x*R(n-1,1)*R(1,k) for n > 1, k > 0 with R(1,k) = Bell(k) for k > 0. The same recursion seems to work for self-convolution of any other sequence. - _Mikhail Kurkov_, Apr 05 2025 %e A357583 Triangle T(n, k) starts: %e A357583 [0] 1; %e A357583 [1] 0, 1; %e A357583 [2] 0, 2, 1; %e A357583 [3] 0, 5, 4, 1; %e A357583 [4] 0, 15, 14, 6, 1; %e A357583 [5] 0, 52, 50, 27, 8, 1; %e A357583 [6] 0, 203, 189, 113, 44, 10, 1; %e A357583 [7] 0, 877, 764, 471, 212, 65, 12, 1; %e A357583 [8] 0, 4140, 3311, 2013, 974, 355, 90, 14, 1; %e A357583 [9] 0, 21147, 15378, 8951, 4440, 1790, 550, 119, 16, 1; %p A357583 # Using function PMatrix from A357368. %p A357583 PMatrix(10, combinat[bell]); %Y A357583 Cf. A000110, A129247 (row sums), A007311, A357584 (central terms). %K A357583 nonn,tabl %O A357583 0,5 %A A357583 _Peter Luschny_, Oct 05 2022