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 A093010 #13 Mar 19 2023 21:55:30 %S A093010 1,1,2,1,4,3,1,6,7,4,1,8,14,10,5,1,10,22,22,13,6,1,12,33,40,30,16,7,1, %T A093010 14,45,66,58,38,19,8,1,16,60,100,104,76,46,22,9,1,18,76,146,168,142, %U A093010 94,54,25,10,1,20,95,202,262,242,180,112,62,28,11,1,22,115,272,386,394,316 %N A093010 Triangle, read by rows, such that the convolution of the n-th row with the natural numbers forms the n-th diagonal, for n>=0, where each row begins with 1. %C A093010 Row sums form A000713, the number of partitions of n into parts of 3 kinds. Antidiagonal sums form A000990, the number of 2-line partitions of n. %F A093010 T(n, k) = sum_{j=0..k} (k-j+1)*T(n-k, j), with T(0, n) = 1 for all n>=0. %F A093010 A000713(n) = sum_{k=0..n} T(n, k) (row sums). %F A093010 A000990(n) = sum_{k=0..floor(n/2)} T(n-k, k) (antidiagonal sums). %e A093010 T(7,3) = 66 = 1*4+8*3+14*2+10*1 = T(4,0)*4+T(4,1)*3+T(4,2)*2+T(4,3)*1; this is also the third term of the 4th-diagonal. %e A093010 The 6th antidiagonal is {1,10,14,4}, which has a sum of 29 = A000990(6) = number of 2-line partitions of 6. %e A093010 Rows begin: %e A093010 {1}, %e A093010 {1,2}, %e A093010 {1,4,3}, %e A093010 {1,6,7,4}, %e A093010 {1,8,14,10,5}, %e A093010 {1,10,22,22,13,6}, %e A093010 {1,12,33,40,30,16,7}, %e A093010 {1,14,45,66,58,38,19,8}, %e A093010 {1,16,60,100,104,76,46,22,9}, %e A093010 {1,18,76,146,168,142,94,54,25,10}, %e A093010 {1,20,95,202,262,242,180,112,62,28,11}, %e A093010 {1,22,115,272,386,394,316,218,130,70,31,12},... %o A093010 (PARI) T(n,k)=if(n<k || k<0,0,if(k==0,1,sum(j=0,min(k,n-k),(k-j+1)*T(n-k,j)))) %Y A093010 Cf. A000713, A000990, A092905. %K A093010 nonn,tabl %O A093010 0,3 %A A093010 _Paul D. Hanna_, Mar 14 2004