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A243621 Numbers n whose digital sum equals the number of bits in its binary expansion. Repeated digits in decimal expansion are not allowed. 1
1, 2, 13, 23, 42, 51, 60, 70, 106, 124, 134, 143, 152, 170, 206, 215, 251, 261, 270, 306, 315, 324, 342, 351, 360, 405, 423, 432, 450, 504, 514, 523, 532, 541, 604, 613, 631, 640, 703, 712 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Subset of A243615.

LINKS

Andreas Boe, Table of n, a(n) for n = 1..10000

EXAMPLE

51 -> 5+1=6   51=110011 -> Six bits.

MATHEMATICA

Select[Range[750], Total[IntegerDigits[#]]==IntegerLength[#, 2]&&Max[ DigitCount[ #]]==1&] (* Harvey P. Dale, Mar 22 2015 *)

PROG

isok(n) = (sumdigits(n) == #binary(n)) && (v=digits(n)) && (#v == #vecsort(v, , 8)); \\ Michel Marcus, Jun 08 2014

CROSSREFS

Cf. A243615 (same principle but allows repetition of figures).

Sequence in context: A243615 A243617 A045389 * A195190 A215390 A285789

Adjacent sequences:  A243618 A243619 A243620 * A243622 A243623 A243624

KEYWORD

nonn,base

AUTHOR

Andreas Boe, Jun 07 2014

STATUS

approved

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Last modified May 10 14:44 EDT 2021. Contains 343773 sequences. (Running on oeis4.)