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A243617
Numbers whose sum of digits equals the number of bits in its binary expansion. No zeros allowed in the digital expansion.
2
1, 2, 13, 23, 33, 42, 51, 115, 124, 134, 143, 152, 161, 215, 224, 233, 242, 251, 261, 315, 324, 333, 342, 351, 414, 423, 432, 441, 514, 523, 532, 541, 613, 622, 631, 712, 721, 811, 1118, 1127, 1136, 1145, 1154, 1163, 1172, 1181, 1217, 1226, 1235, 1244
OFFSET
1,2
COMMENTS
This sequence is a subsequence of A243615.
EXAMPLE
42 -> 4+2=6, 42=101010_2 -> 6 bits.
PROG
(PARI) isok(n) = (sumdigits(n) == #binary(n)) && (vecmin(digits(n)) != 0); \\ Michel Marcus, Jun 08 2014
CROSSREFS
Cf. A243615 (same principle, but zeros allowed in digital expansion).
Sequence in context: A234218 A171794 A243615 * A045389 A243621 A195190
KEYWORD
nonn,base
AUTHOR
Andreas Boe, Jun 07 2014
STATUS
approved