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 A144172 #2 Mar 30 2012 17:25:32 %S A144172 1,1,1,1,1,2,0,1,2,4,1,0,2,4,7,0,1,0,4,7,14,0,0,2,0,7,14,26,1,0,0,4,0, %T A144172 14,26,49,0,1,0,0,7,0,26,49,94,0,0,2,0,0,14,0,49,94,177,0,0,0,4,0,0, %U A144172 26,0,94,177,336,0,0,0,0,7,0,0,49,0,177,336,637 %N A144172 Eigentriangle, row sums = A076739, the number of compositions into Fibonacci numbers. %C A144172 Row sums = A076739 starting with offset 1: (1, 2, 4, 7, 14, 26, 49,...). %C A144172 Left border = A010056, the characteristic function of the Fibonacci numbers Starting with offset 1: (1, 1, 1, 0, 1,...). %C A144172 Sum of n-th row terms = rightmost term of next row. %C A144172 Right border = A076739. %F A144172 T(n,k) = A010056(n-k+1)*A076739(k-1). A010056, the characteristic function of the Fibonacci numbers, starts with offset 1: (1, 1, 1, 0, 1,...). A076739(k-1), the INVERTi transform of (1, 1, 1, 0, 1,...) starts with offset 0: (1, 1, 2, 4, 7, 14,...). %e A144172 First few rows of the triangle = %e A144172 1; %e A144172 1, 1; %e A144172 1, 1, 2; %e A144172 0, 1, 2, 4; %e A144172 1, 0, 2, 4, 7; %e A144172 0, 1, 0, 4, 7, 14; %e A144172 0, 0, 2, 0, 7, 14, 26; %e A144172 1, 0, 0, 4, 0, 14, 26, 49; %e A144172 0, 1, 0, 0, 7, 0, 26, 49, 94; %e A144172 0, 0, 2, 0, 0, 14, 0, 49, 94, 177; %e A144172 0, 0, 0, 4, 0, 0, 26, 0, 94, 177, 336; %e A144172 0, 0, 0, 0, 7, 0, 0, 49, 0, 177, 336, 637; %e A144172 1, 0, 0, 0, 0, 14, 0, 0, 94, 0, 336, 637, 1206; %e A144172 ... %e A144172 Example: row 5 = (1, 0, 2, 4, 7) = termwise product of (1, 0, 1, 1, 1) and (1, 1, 2, 4, 7). %Y A144172 A076739, Cf. A010056 %K A144172 nonn,tabl %O A144172 1,6 %A A144172 _Gary W. Adamson_, Sep 12 2008