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 A193917 #16 Mar 30 2012 18:57:39 %S A193917 1,1,1,1,2,3,2,3,6,9,3,5,9,15,24,5,8,15,24,40,64,8,13,24,39,64,104, %T A193917 168,13,21,39,63,104,168,273,441,21,34,63,102,168,272,441,714,1155,34, %U A193917 55,102,165,272,440,714,1155,1870,3025,55,89,165,267,440,712,1155 %N A193917 Triangular array: the self-fusion of (p(n,x)), where p(n,x)=sum{F(k+1)*x^(n-k) : 0<=k<=n}, where F=A000045 (Fibonacci numbers). %C A193917 See A193722 for the definition of fusion of two sequences of polynomials or triangular arrays. (Fusion is defined at A193822; fission, at A193742; see A202503 and A202453 for infinite-matrix representations of fusion and fission.) %C A193917 First five rows of P (triangle of coefficients of polynomials p(n,x)): %C A193917 1 %C A193917 1...1 %C A193917 1...1...2 %C A193917 1...1...2...3 %C A193917 1...1...2...3...5 %C A193917 First eight rows of A193917: %C A193917 1 %C A193917 1...1 %C A193917 1...2...3 %C A193917 2...3...6...9 %C A193917 3...5...9...15...24 %C A193917 5...8...15..24...40...64 %C A193917 8...13..24..39...64...104..168 %C A193917 13..21..39..63...104..168..273..441 %C A193917 ... %C A193917 col 1: A000045 %C A193917 col 2: A000045 %C A193917 col 3: A022086 %C A193917 col 4: A022086 %C A193917 col 5: A022091 %C A193917 col 6: A022091 %C A193917 col 7: A022355 %C A193917 col 8: A022355 %C A193917 right edge, w(n,n): A064831 %C A193917 w(n,n-1): A001654 %C A193917 w(n,n-2): A064831 %C A193917 w(n,n-3): A059840 %C A193917 w(n,n-4): A080097 %C A193917 w(n,n-5): A080143 %C A193917 w(n,n-6): A080144 %C A193917 Suppose n is an even positive integer and w(n+1,x) is the polynomial matched to row n+1 of A193917 as in the Mathematica program (and definition of fusion at A193722), where the first row is counted as row 0. %e A193917 First six rows: %e A193917 1 %e A193917 1...1 %e A193917 1...2...3 %e A193917 2...3...6....9 %e A193917 3...5...9....15...24 %e A193917 5...8...15...24...40...64 %t A193917 z = 12; %t A193917 p[n_, x_] := Sum[Fibonacci[k + 1]*x^(n - k), {k, 0, n}]; %t A193917 q[n_, x_] := p[n, x]; %t A193917 t[n_, k_] := Coefficient[p[n, x], x^k]; t[n_, 0] := p[n, x] /. x -> 0; %t A193917 w[n_, x_] := Sum[t[n, k]*q[n + 1 - k, x], {k, 0, n}]; w[-1, x_] := 1 %t A193917 g[n_] := CoefficientList[w[n, x], {x}] %t A193917 TableForm[Table[Reverse[g[n]], {n, -1, z}]] %t A193917 Flatten[Table[Reverse[g[n]], {n, -1, z}]] (* A193917 *) %t A193917 TableForm[Table[g[n], {n, -1, z}]] %t A193917 Flatten[Table[g[n], {n, -1, z}]] (* A193918 *) %Y A193917 Cf. A193722, A064831, A193918, A194000, A194001. %K A193917 nonn,tabl %O A193917 0,5 %A A193917 _Clark Kimberling_, Aug 09 2011