A303215 A(n,k) is the n-th index of a Fibonacci number with exactly k prime factors (counted with multiplicity); square array A(n,k), n>=1, k>=1, read by antidiagonals.
3, 8, 4, 6, 9, 5, 20, 15, 10, 7, 18, 27, 16, 14, 11, 12, 44, 28, 21, 19, 13, 30, 40, 45, 32, 25, 22, 17, 54, 42, 50, 57, 52, 33, 26, 23, 24, 78, 56, 64, 63, 55, 35, 31, 29, 36, 80, 102, 66, 75, 68, 74, 37, 34, 43, 138, 100, 88, 128, 70, 92, 69, 77, 38, 41, 47
Offset: 1
Examples
Square array A(n,k) begins: 3, 8, 6, 20, 18, 12, 30, 54, 24, 36, ... 4, 9, 15, 27, 44, 40, 42, 78, 80, 100, ... 5, 10, 16, 28, 45, 50, 56, 102, 88, 114, ... 7, 14, 21, 32, 57, 64, 66, 128, 110, 165, ... 11, 19, 25, 52, 63, 75, 70, 130, 112, 174, ... 13, 22, 33, 55, 68, 92, 81, 135, 184, 256, ... 17, 26, 35, 74, 69, 95, 104, 147, 186, 266, ... 23, 31, 37, 77, 76, 99, 105, 154, 189, 273, ... 29, 34, 38, 85, 91, 116, 136, 170, 196, 282, ... 43, 41, 39, 87, 98, 117, 148, 171, 225, 296, ...
Links
- Alois P. Heinz, Antidiagonals n = 1..16, flattened
Crossrefs
Programs
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Maple
F:= combinat[fibonacci]: with(numtheory): A:= proc() local h, p, q; p, q:= proc() [] end, 2; proc(n, k) while nops(p(k)) -
Mathematica
A[n_, k_] := Module[{h, p, q = 2}, p[k] = {}; While[Length[p[k]]
Comments