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A076153 Numbers n such that Omega(n) = Omega(n-1)^2, where Omega(m) (A001222) denotes the number of prime factors of m, counted with multiplicity. 2
3, 16, 36, 40, 56, 88, 135, 156, 184, 204, 210, 220, 248, 250, 260, 296, 306, 315, 328, 330, 340, 342, 372, 414, 459, 472, 490, 516, 536, 546, 580, 584, 636, 650, 686, 690, 708, 714, 732, 735, 738, 804, 808, 819, 836, 850, 852, 870, 872, 940, 950, 966, 975, 996, 999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

Omega(996) = 2^2 = Omega(995)^2, so 996 is a term of the sequence.

MATHEMATICA

Select[Range[1000], PrimeOmega[#]==PrimeOmega[#-1]^2&] (* Ray Chandler, Jul 07 2015 *)

CROSSREFS

Similar to A109287; after a(1)=3 next difference is a(101)=1792 whereas A109287(100)=1794. - Ray Chandler, Mar 20 2007

Cf. A001222.

Sequence in context: A013199 A162419 A322191 * A031302 A217130 A173390

Adjacent sequences:  A076150 A076151 A076152 * A076154 A076155 A076156

KEYWORD

easy,nonn

AUTHOR

Joseph L. Pe, Oct 31 2002

EXTENSIONS

Edited by Ray Chandler, Mar 20 2007

STATUS

approved

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Last modified June 12 17:33 EDT 2021. Contains 344959 sequences. (Running on oeis4.)