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 A066617 Composites of form prime+1 containing a record number of prime factors. 1
 4, 8, 24, 32, 128, 384, 1152, 3584, 5120, 6144, 8192, 73728, 131072, 524288, 5505024, 10616832, 14680064, 18874368, 109051904, 169869312, 654311424, 738197504, 2147483648, 21474836480, 51539607552, 824633720832, 3710851743744 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The sequence contains all numbers of the form (Mersenne Prime)+1 as a subset. - Hugo Pfoertner, Sep 10 2004 LINKS Table of n, a(n) for n=1..27. EXAMPLE a(19)=109051904=13*2^23: 24 prime factors, a(20)=169869312=3^4*2^21: 25 prime factors, a(21)=654311424=13*3*2^24: 26 prime factors. a(19)-1, a(20)-1 and a(21)-1 are primes. PROG (PARI) {A066617(a, b) = local(p, c, d); forprime(p=a, b, d=bigomega(p+1); if(d>c, c=d; print1(p+1, ", ")))} A066617(3, 10^7) CROSSREFS Cf. Mersenne Primes + 1: A072868(n)=A000668(n)+1. Sequence in context: A291548 A212019 A075708 * A272272 A024589 A062015 Adjacent sequences: A066614 A066615 A066616 * A066618 A066619 A066620 KEYWORD nonn AUTHOR G. L. Honaker, Jr., Jan 13 2002 EXTENSIONS More terms from Jason Earls, Jan 15 2002 More terms from Hugo Pfoertner, Sep 10 2004 a(24)-a(27) from Donovan Johnson, Dec 08 2009 STATUS approved

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Last modified November 29 17:03 EST 2023. Contains 367445 sequences. (Running on oeis4.)