A359091 a(n) is the index of the smallest n-gonal number with binary weight n.

6, 13, 9, 10, 24, 58, 34, 55, 67, 151, 134, 187, 201, 691, 350, 623, 1082, 1870, 2302, 3171, 5017, 13863, 13230, 6663, 24357, 50397, 35604, 60347, 63810, 107019, 181517, 365595, 624858, 1345485, 1002585, 1969415, 1191179, 7651731, 4592173, 7279863, 7403686, 17923182

Offset

3,1

Links

Table of n, a(n) for n=3..44.

Eric Weisstein's World of Mathematics, Polygonal Number

Index entries for sequences related to binary expansion of n

Mathematica

p[n_, k_] := (n - 2)*k*(k - 1)/2 + k; a[n_] := Module[{k = 1}, While[DigitCount[p[n, k], 2, 1] != n, k++]; k]; Array[a, 30, 3] (* Amiram Eldar, Dec 17 2022 *)

Crossrefs

Cf. A000120, A211201, A231897, A359092.

Sequence in context: A229336 A363755 A070396 * A130012 A265740 A090324

Adjacent sequences: A359088 A359089 A359090 * A359092 A359093 A359094

Keyword

nonn,base

Author

Ilya Gutkovskiy, Dec 16 2022

Status

approved