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 A111438 #5 Mar 30 2012 18:40:29 %S A111438 1,1,1,3,21,987,2178309,10610209857723,155576970220531065681649693, %T A111438 33449372971981195681356806732944396691005381570580873 %N A111438 Fibonacci(heptanacci(n)), restricted to nonzero heptanacci numbers. %F A111438 a(n) = A000045(A066178(n)). %e A111438 a(0) = Fibonacci(heptanacci(0)) = A000045(A066178(0)) = A000045(1) = 1. %e A111438 a(1) = Fibonacci(heptanacci(1)) = A000045(A066178(1)) = A000045(1) = 1. %e A111438 a(2) = Fibonacci(heptanacci(2)) = A000045(A066178(2)) = A000045(2) = 1. %e A111438 a(3) = Fibonacci(heptanacci(3)) = A000045(A066178(3)) = A000045(4) = 3. %e A111438 a(4) = Fibonacci(heptanacci(4)) = A000045(A066178(4)) = A000045(8) = 21. %e A111438 a(5) = Fibonacci(heptanacci(5)) = A000045(A066178(5)) = A000045(16) = 987. %e A111438 a(6) = A000045(A066178(6)) = A000045(32) = 2178309. %e A111438 a(7) = A000045(A066178(7)) = A000045(64) = 10610209857723. %e A111438 a(8) = A000045(A066178(8)) = A000045(127) = 155576970220531065681649693. %Y A111438 Cf. A000045, A001592, A066178, A007570. %K A111438 easy,nonn %O A111438 0,4 %A A111438 _Jonathan Vos Post_, Nov 14 2005 %E A111438 Corrected by _T. D. Noe_, Nov 16 2006