A152088 Positive integers k that when written in binary have exactly the same number of (non-leading) 0's as the number of divisors of k.

19, 33, 34, 43, 49, 53, 69, 74, 79, 82, 103, 107, 109, 141, 142, 166, 177, 178, 201, 202, 209, 226, 261, 268, 292, 295, 299, 301, 302, 309, 314, 327, 334, 339, 341, 346, 355, 358, 362, 367, 379, 388, 391, 395, 398, 403, 422, 431, 439, 443, 451, 453, 454, 458

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Example

34 written in binary is 100010, which has four 0's. Also, 34 has 4 divisors (1,2,17,34). Since the number of binary 0's equals the number of divisors, then 34 is included in this sequence.

Mathematica

Select[Range[500], DigitCount[#, 2, 0] == DivisorSigma[0, #] &] (* Amiram Eldar, Dec 28 2019 *)

Crossrefs

Cf. A000005, A023416, A071593, A080791.

Sequence in context: A061962 A272910 A116168 * A372427 A362410 A106527

Adjacent sequences: A152085 A152086 A152087 * A152089 A152090 A152091

Keyword

nonn,base

Author

Leroy Quet, Nov 23 2008

Extensions

Extended by Ray Chandler, Nov 26 2008

Status

approved