A280967 Vampire numbers (definition 1) in binary: n has a nontrivial factorization using n's bits.

159, 175, 287, 303, 315, 318, 319, 343, 350, 351, 375, 567, 574, 575, 591, 603, 606, 623, 627, 630, 636, 638, 679, 686, 687, 699, 700, 702, 735, 750, 763, 765, 1127, 1134, 1135, 1148, 1150, 1167, 1179, 1182, 1183, 1203, 1206, 1212, 1215, 1239, 1243, 1246, 1247, 1251, 1254, 1260, 1271, 1272

Offset

1,1

Comments

Nontrivial means that there must be at least two factors.

Links

Ely Golden, Table of n, a(n) for n = 1..10000

Ely Golden, General program for generating vampire number sequences

Example

175 is a member as 175 = 7 * 25 = 10101111_2 = 111_2 * 11001_2
5887 is a member as 5887 = 7 * 29 * 29 = 1011011111111_2 = 111_2 * 11101_2 * 11101_2

Crossrefs

Cf. A020342

Sequence in context: A303811 A207146 A045260 * A192173 A093472 A270304

Adjacent sequences: A280964 A280965 A280966 * A280968 A280969 A280970

Keyword

nonn,base

Author

Ely Golden, Jan 11 2017

Status

approved