A115168 Even numbers n such that n-2 and n+2 have the same number of prime divisors with multiplicity.

8, 10, 12, 24, 36, 38, 58, 60, 68, 84, 86, 100, 102, 110, 112, 120, 134, 138, 144, 154, 172, 178, 184, 188, 204, 216, 230, 240, 244, 276, 284, 288, 300, 302, 320, 342, 346, 360, 368, 372, 374, 378, 384, 394, 396, 404, 408, 428, 432, 436, 440, 456, 466, 472

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Maple

g(n) = forstep(x=4, n, 2, p1=bigomega(x-2); p2=bigomega(x+2); if(p1==p2, print(x", ")))

Mathematica

Select[Range[4, 472, 2],  PrimeOmega[# - 2] ==  PrimeOmega[# + 2] &] (* Amiram Eldar, Sep 23 2019 *)
2*Mean/@SequencePosition[Table[PrimeOmega[n], {n, 2, 500, 2}], {x_, _, x_}] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 20 2021 *)

Crossrefs

Sequence in context: A114873 A114621 A174156 * A303223 A112549 A112585

Adjacent sequences: A115165 A115166 A115167 * A115169 A115170 A115171

Keyword

easy,nonn

Author

Cino Hilliard, Mar 03 2006

Status

approved