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A281597 Numbers k such that A001221(k) = A001221(A000041(k)). 3
1, 2, 3, 4, 5, 12, 13, 14, 15, 30, 42, 60, 65, 76, 85, 87, 92, 93, 95, 99, 102, 105, 112, 114, 123, 143, 146, 156, 157, 161, 190, 195, 198, 203, 210, 218, 234, 235, 238, 258, 275, 285, 287, 291, 308, 321, 357, 360, 370, 380, 385, 388, 396, 398, 408, 410, 420 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers k such that the number of distinct prime divisors of k is equal to the number of distinct prime divisors of the number of partitions of k.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..940 (terms 1..100 from Colin Barker, terms 101..196 from Indranil Ghosh)

MATHEMATICA

Select[Range[2000], PrimeNu[#]==PrimeNu[PartitionsP[#]] &] (* Indranil Ghosh, Mar 09 2017 *)

PROG

(PARI) select(n->omega(n)==omega(numbpart(n)), vector(500, n, n))

CROSSREFS

Cf. A000041, A001221, A281598, A281599.

Sequence in context: A240304 A325684 A339453 * A039007 A050745 A077375

Adjacent sequences:  A281594 A281595 A281596 * A281598 A281599 A281600

KEYWORD

nonn

AUTHOR

Colin Barker, Jan 25 2017

STATUS

approved

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Last modified October 16 05:41 EDT 2021. Contains 348035 sequences. (Running on oeis4.)