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A161001 Those positive integers n that when read in binary contains runs of 0's and 1's being of distinct lengths, the list of lengths forming a permutation of some number of consecutive positive integers. 2
1, 3, 4, 6, 7, 15, 24, 28, 31, 35, 39, 49, 55, 57, 59, 63, 112, 120, 127, 255, 391, 399, 451, 463, 480, 483, 487, 496, 511, 536, 540, 560, 572, 624, 632, 776, 782, 784, 798, 880, 888, 900, 902, 912, 926, 944, 956, 964, 966, 968, 974, 984, 988, 1023, 1984, 2016 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Think of binary n as a string S of 0's and 1's. By a "run" of 0's or 1's, it is meant either a substring all of contiguous 0's, each run bounded by 1's or the edge of S; or a substring all of contiguous 1's, each run bounded by 0's or the edge of S.

LINKS

Table of n, a(n) for n=1..56.

EXAMPLE

451 in binary is 111000011. This contains a run of three 1's, followed by a run of four 0's, followed by a run of two 1's. Since (3,4,2) is a permutation of some number of consecutive positive integers (2,3,4), then 451 is in the sequence.

CROSSREFS

Cf. A161000.

Sequence in context: A058639 A253888 A289811 * A168170 A290115 A225794

Adjacent sequences:  A160998 A160999 A161000 * A161002 A161003 A161004

KEYWORD

base,nonn

AUTHOR

Leroy Quet, Jun 01 2009

EXTENSIONS

Extended by Ray Chandler, Jun 13 2009

STATUS

approved

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Last modified June 1 09:53 EDT 2020. Contains 334762 sequences. (Running on oeis4.)