A166456 Row sums of triangle A166455.

1, 2, 6, 12, 30, 60, 124, 248, 510, 1020, 2044, 4088, 8188, 16376, 32760, 65520, 131070, 262140, 524284, 1048568, 2097148, 4194296, 8388600, 16777200, 33554428, 67108856, 134217720, 268435440, 536870904, 1073741808, 2147483632, 4294967264, 8589934590, 17179869180

Offset

0,2

Links

Table of n, a(n) for n=0..33.

Formula

a(n) = 2^(n+1) - A001316(n). - R. J. Mathar, Oct 30 2009

Example

a(3) = 12 = (1 + 5 + 5 + 1).

Mathematica

a[n_] := 2^(n+1) - 2^DigitCount[n, 2, 1]; Array[a, 31, 0] (* Amiram Eldar, Aug 01 2023 *)

Prog

(Python)
def A000120(n):
    a = 0
    while n > 0:
        a += n % 2
        n //= 2
    return a
def A001316(n):
    return 2**A000120(n)
def A166456(n):
    return 2**(n+1) - A001316(n)
print([A166456(n) for n in range(80)])
# R. J. Mathar, Oct 30 2009

Crossrefs

Cf. A001316, A166455.

Sequence in context: A005417 A058215 A330542 * A162214 A309728 A100071

Adjacent sequences: A166453 A166454 A166455 * A166457 A166458 A166459

Keyword

nonn

Author

Gary W. Adamson, Oct 14 2009

Extensions

Extended by R. J. Mathar, Oct 30 2009

Status

approved