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A091375 Numbers having more prime factors than the value of their smallest prime factor. 6
8, 12, 16, 18, 20, 24, 28, 30, 32, 36, 40, 42, 44, 48, 50, 52, 54, 56, 60, 64, 66, 68, 70, 72, 76, 78, 80, 81, 84, 88, 90, 92, 96, 98, 100, 102, 104, 108, 110, 112, 114, 116, 120, 124, 126, 128, 130, 132, 135, 136, 138, 140, 144, 148, 150, 152, 154, 156, 160, 162 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A091371(a(n)) < 0: A001222(a(n))>A020639(a(n)).

Numbers of the form m*i + n*j = k*(i+j), where i and j are > 1. - Giovanni Teofilatto, Aug 29 2007

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10438

MATHEMATICA

Select[Range@ 162, Length@ Flatten[Table[#1, {#2}] & @@@ #] > #[[1, 1]] &@ FactorInteger@ # &] (* Michael De Vlieger, Jul 06 2016 *)

PROG

(PARI) is(n)=n>7 && bigomega(n) > factor(n)[1, 1] \\ Charles R Greathouse IV, Jul 06 2016

(PARI) bigomegaAtLeast(n, k, startAt=2)=if(k<3, return(if(k==2, n>1&&!isprime(n), k==0||n>1))); forprime(p=startAt, logint(n, k), if(n%p==0, k-=valuation(n, p); n/=p^valuation(n, p); return(bigomegaAtLeast(n, k)))); 0

is(n)=if(n%2==0, return(bigomegaAtLeast(n/2, 2))); if(n%3==0, return(bigomegaAtLeast(n/3, 3, 3))); if(n<9, return(0)); forprime(p=5, log(n)/lambertw(log(n)), if(n%p==0, return(bigomegaAtLeast(n/p, p, p)))); 0 \\ Charles R Greathouse IV, Jul 06 2016

CROSSREFS

Cf. A091372, A091376, A091377.

Sequence in context: A033942 A111087 A166083 * A282671 A192991 A083348

Adjacent sequences:  A091372 A091373 A091374 * A091376 A091377 A091378

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jan 04 2004

EXTENSIONS

Missing a(10001)-a(10424) inserted into b-file by Andrew Howroyd, Feb 25 2018

STATUS

approved

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Last modified February 23 12:03 EST 2019. Contains 320431 sequences. (Running on oeis4.)