A106264 Diagonal sums of number triangle A106262.

1, 0, 1, 2, 2, 4, 2, 4, 6, 7, 7, 8, 14, 10, 13, 12, 15, 19, 22, 22, 23, 25, 25, 44, 44, 40, 28, 50, 44, 54, 52, 55, 50, 66, 53, 72, 83, 80, 58, 73, 82, 110, 114, 123, 127, 113, 91, 112, 158, 137, 117, 122, 152, 135, 166, 160, 211, 206, 171, 219, 240, 201, 188, 194, 236

Offset

0,4

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Formula

a(n) = Sum_{k=0..floor(n/2)} ( 2^(n-2*k) mod (k+2) ).

Mathematica

Table[Sum[Mod[2^(n-2*k), k+2], {k, 0, Floor[n/2]}], {n, 0, 80}] (* G. C. Greubel, Jan 10 2023 *)

Prog

(Magma) [(&+[2^(n-2*k) mod (k+2): k in [0..Floor(n/2)]]): n in [0..80]]; // G. C. Greubel, Jan 10 2023
(SageMath)
def A106264(n): return sum( (2^(n-2*k)%(k+2)) for k in range(n//2+1) )
[A106264(n) for n in range(81)] # G. C. Greubel, Jan 10 2023

Crossrefs

Cf. A106262.

Sequence in context: A306743 A140821 A063789 * A278535 A152423 A233765

Adjacent sequences: A106261 A106262 A106263 * A106265 A106266 A106267

Keyword

easy,nonn

Author

Paul Barry, Apr 28 2005

Status

approved