cp's OEIS Frontend

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.

A152931 Number of sets (in the Hausdorff metric geometry) at each location between two sets defining a polygonal configuration consisting of three m-gonal polygonal components chained with string components of length 2 as m varies.

Original entry on oeis.org

4393, 80361, 1425131, 25671393, 459934921, 8258011407, 148150698209, 2658683875329, 47706585218947, 856070631915129, 15361490875216193, 275651271699299271, 4946357927482614361, 88758815221749418713, 1592712152944203460571, 28580061055811939151057
Offset: 2

Views

Author

Steven Schlicker, Dec 15 2008

Keywords

Crossrefs

Programs

  • Maple
    with(combinat): a := proc(n) local aa, b, c, d, lambda, delta, R, S, F, L, k, l: k:=3: l:=2: F := t -> fibonacci(t): L := t -> fibonacci(t-1)+fibonacci(t+1): aa := (n, l) -> L(2*n)*F(l-2)+F(2*n+2)*F(l-1): b := (n, l) -> L(2*n)*F(l-1)+F(2*n+2)*F(l): c := (n, l) -> F(2*n+2)*F(l-2)+F(n+2)^2*F(l-1): d := (n, l) -> F(2*n+2)*F(l-1)+F(n+2)^2*F(l): lambda := (n,l) -> (d(n, l)+aa(n, l)+sqrt((d(n, l)-aa(n, l))^2+4*b(n, l)*c(n, l)))*(1/2): delta := (n,l) -> (d(n, l)+aa(n, l)-sqrt((d(n, l)-aa(n, l))^2+4*b(n, l)*c(n, l)))*(1/2): R := (n,l) -> ((lambda(n, l)-d(n, l))*L(2*n)+b(n, l)*F(2*n+2))/(2*lambda(n, l)-d(n, l)-aa(n, l)): S := (n,l) -> ((lambda(n, l)-aa(n, l))*L(2*n)-b(n, l)*F(2*n+2))/(2*lambda(n, l)-d(n, l)-aa(n, l)): simplify(R(n, l)*lambda(n, l)^(k-1)+S(n, l)*delta(n, l)^(k-1)); end proc;
  • Mathematica
    LinearRecurrence[{13,104,-260,-260,104,13,-1},{4393,80361,1425131,25671393,459934921,8258011407,148150698209},20] (* Harvey P. Dale, Feb 18 2024 *)