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A097214 Numbers m such that A076078(m) = m, where A076078(m) equals the number of sets of distinct positive integers with a least common multiple of m. 3
1, 2, 4, 8, 10, 16, 32, 44, 64, 128, 184, 256, 512, 752, 1024, 2048, 4096, 8192, 12224, 16384, 32768, 49024, 61064, 65536, 131072, 262144, 524288, 981520, 1048576, 2097152, 4194304, 8388608, 12580864, 16777216, 33554432, 67108864, 134217728 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Contains all powers of 2 (A000079). Union of A000079 and A097215.

If 3*2^k - 1 is prime then 2^k*(3*2^k-1) is in the sequence. So 2^A002235*(3*2^A002235-1) is a subsequence of this sequence. - Farideh Firoozbakht, Aug 06 2005

LINKS

Jinyuan Wang, Table of n, a(n) for n = 1..334

EXAMPLE

A total of 10 sets of distinct positive integers have a least common multiple of 10: {1,2,5}, {1,2,5,10}, {1,2,10}, {1,5,10}, {1,10}, {2,5}, {2,5,10}, {2,10}, {5,10} and {10}. Hence 10 is in the sequence.

CROSSREFS

Cf. A076078, A097215.

Cf. A002235.

Sequence in context: A335404 A271816 A097210 * A045579 A177050 A276772

Adjacent sequences:  A097211 A097212 A097213 * A097215 A097216 A097217

KEYWORD

nonn

AUTHOR

Matthew Vandermast, Aug 12 2004

EXTENSIONS

a(26) corrected by Jinyuan Wang, Feb 11 2020

STATUS

approved

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Last modified March 7 00:48 EST 2021. Contains 341851 sequences. (Running on oeis4.)