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A106264
Diagonal sums of number triangle A106262.
2
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
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
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Apr 28 2005
STATUS
approved