A038461 Sums of 10 distinct powers of 2.

1023, 1535, 1791, 1919, 1983, 2015, 2031, 2039, 2043, 2045, 2046, 2559, 2815, 2943, 3007, 3039, 3055, 3063, 3067, 3069, 3070, 3327, 3455, 3519, 3551, 3567, 3575, 3579, 3581, 3582, 3711, 3775, 3807, 3823, 3831, 3835, 3837, 3838, 3903

Offset

1,1

Links

Ivan Neretin, Table of n, a(n) for n = 1..10000

Robert Baillie, Summing the curious series of Kempner and Irwin, arXiv:0806.4410 [math.CA], 2008-2015. See p. 18 for Mathematica code irwinSums.m.

Formula

Sum_{n>=1} 1/a(n) = 1.386312271262110321181505974797071257205562524228381227122302929089588534920... (calculated using Baillie's irwinSums.m, see Links). - Amiram Eldar, Feb 14 2022

Mathematica

Select[Range[4000], DigitCount[#, 2, 1] == 10 &] (* Amiram Eldar, Feb 14 2022 *)

Prog

(PARI) isok(n) = hammingweight(n) == 10; \\ Michel Marcus, Feb 29 2016
(Python)
from itertools import islice
def A038461_gen(): # generator of terms
    yield (n:=1023)
    while True: yield (n:=n^((a:=-n&n+1)|(a>>1)) if n&1 else ((n&~(b:=n+(a:=n&-n)))>>a.bit_length())^b)
A038461_list = list(islice(A038461_gen(), 20)) # Chai Wah Wu, Mar 10 2025

Crossrefs

Base 2 interpretation of A038452.

Cf. A000079, A018900, A014311, A014312, A014313, A023688, A023689, A023690, A023691 (Hamming weight = 1, 2, ..., 9).

Sequence in context: A145589 A031969 A166512 * A380831 A338704 A158421

Adjacent sequences: A038458 A038459 A038460 * A038462 A038463 A038464

Keyword

nonn,base,easy

Author

Olivier Gérard

Extensions

Offset changed to 1 by Ivan Neretin, Feb 28 2016

Status

approved