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A359514
Number of compositions (ordered partitions) of n into at most 2 positive Fibonacci numbers (with a single type of 1).
5
1, 1, 2, 3, 3, 3, 3, 2, 3, 2, 3, 2, 0, 3, 2, 2, 3, 0, 2, 0, 0, 3, 2, 2, 2, 0, 3, 0, 0, 2, 0, 0, 0, 0, 3, 2, 2, 2, 0, 2, 0, 0, 3, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 3, 2, 2, 2, 0, 2, 0, 0, 2, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 2, 2, 0, 2
OFFSET
0,3
LINKS
FORMULA
a(n) = Sum_{k=0..2} A121548(n,k). - Alois P. Heinz, Jan 03 2023
MAPLE
g:= proc(n) g(n):= (t-> issqr(t+4) or issqr(t-4))(5*n^2) end:
b:= proc(n, t) option remember; `if`(n=0, 1, `if`(t<1, 0,
add(`if`(g(j), b(n-j, t-1), 0), j=1..n)))
end:
a:= n-> b(n, 2):
seq(a(n), n=0..94); # Alois P. Heinz, Jan 03 2023
MATHEMATICA
g[n_] := IntegerQ@Sqrt[# + 4] || IntegerQ@Sqrt[# - 4]&[5 n^2];
b[n_, t_] := b[n, t] = If[n == 0, 1, If[t < 1, 0, Sum[If[g[j], b[n - j, t - 1], 0], {j, 1, n}]]];
a[n_] := b[n, 2];
Table[a[n], {n, 0, 94}] (* Jean-François Alcover, May 26 2023, after Alois P. Heinz *)
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jan 03 2023
STATUS
approved