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A272044 Numbers n such that n and n^2+1 have the same number of prime factors (including multiplicities). 2
2, 9, 15, 18, 22, 25, 27, 34, 35, 39, 46, 49, 51, 58, 62, 63, 65, 69, 70, 75, 85, 86, 95, 98, 105, 106, 121, 125, 132, 138, 141, 145, 147, 148, 153, 158, 159, 166, 169, 172, 174, 178, 194, 201, 202, 205, 209, 212, 214, 219, 221, 226, 254, 262, 274, 282, 285, 289, 298, 299 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

FORMULA

Numbers n such that bigomega(n) = bigomega(n^2+1).

MAPLE

with(numtheory): A272044:=n->`if`(bigomega(n)=bigomega(n^2+1), n, NULL): seq(A272044(n), n=1..500); # Wesley Ivan Hurt, Apr 19 2016

MATHEMATICA

Select[Range@ 300, PrimeOmega[#^2 + 1] == PrimeOmega@ # &] (* Michael De Vlieger, Apr 19 2016 *)

PROG

(PARI) is(n)=bigomega(n)==bigomega(n^2+1) \\ Charles R Greathouse IV, Apr 18 2016

CROSSREFS

Cf. A001222 (bigomega), A193330.

Sequence in context: A076208 A057481 A083288 * A304803 A184531 A063105

Adjacent sequences:  A272041 A272042 A272043 * A272045 A272046 A272047

KEYWORD

nonn

AUTHOR

Benjamin Przybocki, Apr 18 2016

STATUS

approved

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Last modified June 12 19:31 EDT 2021. Contains 344960 sequences. (Running on oeis4.)