A066793 The start of a record-breaking run of consecutive integers with an even number of prime factors.

1, 9, 14, 33, 54, 140, 213, 1934, 35811, 38405, 200938, 389409, 1792209, 5606457, 8405437, 68780189, 880346227, 85910903650, 87635944146, 284340107954, 2195312273836, 2864568747364, 3155591650029

Offset

1,2

Comments

a(21) > 10^12. [From Donovan Johnson, Oct 11 2010]

a(24) > 10^13. - Giovanni Resta, Aug 01 2013

Prime factors counted with multiplicity. - Harvey P. Dale, Sep 06 2022

Links

Table of n, a(n) for n=1..23.

Mathematica

Table[SequencePosition[If[EvenQ[#], 1, 0]&/@PrimeOmega[Range[40000]], PadRight[{}, n, 1], 1][[All, 1]], {n, 14}]//Flatten//Union (* The program generates the first 10 terms of the sequence. *) (* Harvey P. Dale, Sep 06 2022 *)

Crossrefs

Cf. A066794, A175201.

Sequence in context: A272781 A229543 A175201 * A275508 A139055 A294030

Adjacent sequences: A066790 A066791 A066792 * A066794 A066795 A066796

Keyword

nonn

Author

G. L. Honaker, Jr., Jan 18 2002

Extensions

Except for first 4 or 5 terms, computed by Shyam Sunder Gupta, Jan 26 2002

a(12) and a(14) corrected and a(18)-a(20) from Donovan Johnson, Oct 11 2010

a(21)-a(23) from Giovanni Resta, Aug 01 2013

Status

approved