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A281597 Numbers k such that A001221(k) = A001221(A000041(k)). 3


%S 1,2,3,4,5,12,13,14,15,30,42,60,65,76,85,87,92,93,95,99,102,105,112,

%T 114,123,143,146,156,157,161,190,195,198,203,210,218,234,235,238,258,

%U 275,285,287,291,308,321,357,360,370,380,385,388,396,398,408,410,420

%N Numbers k such that A001221(k) = A001221(A000041(k)).

%C 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.

%H Amiram Eldar, <a href="/A281597/b281597.txt">Table of n, a(n) for n = 1..940</a> (terms 1..100 from Colin Barker, terms 101..196 from Indranil Ghosh)

%t Select[Range[2000], PrimeNu[#]==PrimeNu[PartitionsP[#]] &] (* _Indranil Ghosh_, Mar 09 2017 *)

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

%Y Cf. A000041, A001221, A281598, A281599.

%K nonn

%O 1,2

%A _Colin Barker_, Jan 25 2017

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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)