A397148 - OEIS

A397148

Numbers k such that k + omega(k) is prime.

2, 4, 15, 16, 21, 35, 39, 45, 51, 57, 65, 69, 70, 77, 87, 95, 99, 110, 111, 129, 135, 147, 154, 155, 161, 170, 171, 177, 189, 190, 209, 220, 221, 225, 230, 237, 238, 249, 256, 260, 261, 266, 267, 275, 279, 280, 290, 291, 305, 308, 309, 310, 329, 335, 350, 351, 364

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..57.

EXAMPLE

2 is a term, because 2 + omega(2) = 2 + 1 = 3 is prime.

4 is a term, because 4 + omega(4) = 4 + 1 = 5 is prime.

15 is a term, because 15 + omega(15) = 15 + 2 = 17 is prime.

MATHEMATICA

Select[Range[370], PrimeQ[#+PrimeNu[#]] &] (* Stefano Spezia, Jul 15 2026 *)

CROSSREFS