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.

A296478 Decimal expansion of limiting power-ratio for A295950; see Comments.

Original entry on oeis.org

6, 9, 2, 0, 2, 0, 8, 3, 1, 1, 6, 9, 3, 1, 5, 9, 1, 0, 8, 5, 8, 8, 2, 1, 3, 4, 0, 8, 4, 9, 4, 1, 9, 8, 7, 0, 5, 7, 3, 8, 6, 7, 8, 6, 9, 1, 5, 5, 2, 6, 8, 4, 6, 2, 5, 3, 7, 6, 6, 9, 9, 3, 8, 5, 4, 7, 1, 8, 2, 0, 5, 8, 1, 2, 0, 8, 6, 0, 7, 4, 0, 3, 5, 6, 5, 8
Offset: 1

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Author

Clark Kimberling, Jan 05 2018

Keywords

Comments

Suppose that A = (a(n)), for n >= 0, is a sequence, and g is a real number such that a(n)/a(n-1) -> g. The limiting power-ratio for A is the limit as n->oo of a(n)/g^n, assuming that this limit exists. For A = A295950, we have g = (1 + sqrt(5))/2, the golden ratio (A001622). See the guide at A296469 for related sequences.

Examples

			limiting power-ratio = 6.920208311693159108588213408494198705738...
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 4; b[0] = 2; b[1 ] = 3; b[2] = 5;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n];
    j = 1; While[j < 13, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]; (* A295950 *)
    z = 2000; g = GoldenRatio; h = Table[N[a[n]/g^n, z], {n, 0, z}];
    StringJoin[StringTake[ToString[h[[z]]], 41], "..."]
    Take[RealDigits[Last[h], 10][[1]], 120]   (* A296478 *)