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A348073 Numbers k such that omega(k) = 9. 3
223092870, 281291010, 300690390, 340510170, 358888530, 363993630, 380570190, 397687290, 406816410, 417086670, 434444010, 446185740, 455885430, 458948490, 481410930, 485555070, 497668710, 504894390, 512942430, 514083570, 531990690, 538047510, 547777230, 551861310, 562582020 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
562582020 = 2^2 * 3 * 5 * 7 * 11 * 13 * 17 * 19 * 29 is in the sequence as it has 9 distinct prime divisors (namely 2, 3, 5, 7, 11, 13, 17, 19 and 29).
PROG
(PARI) is(n) = omega(n) == 9
(PARI) A246655(lim)=my(v=List(primes([2, lim\=1]))); for(e=2, logint(lim, 2), forprime(p=2, sqrtnint(lim, e), listput(v, p^e))); Set(v)
list(lim, pr=9)=if(pr==1, return(A246655(lim))); my(v=List(), pr1=pr-1, mx=prod(i=1, pr1, prime(i))); forprime(p=prime(pr), lim\mx, my(u=list(lim\p, pr1)); for(i=1, #u, listput(v, p*u[i]))); Set(v) \\ Charles R Greathouse IV, Feb 03 2023
CROSSREFS
Row 9 of A125666.
Sequence in context: A231093 A262559 A199498 * A115343 A258364 A046327
KEYWORD
nonn
AUTHOR
David A. Corneth, Oct 10 2021
STATUS
approved

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Last modified April 18 22:18 EDT 2024. Contains 371782 sequences. (Running on oeis4.)