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A079890 Least number > n having one more prime factor than n, not necessarily distinct. 7
2, 4, 4, 8, 6, 8, 9, 16, 12, 12, 14, 16, 14, 18, 18, 32, 21, 24, 21, 24, 27, 27, 25, 32, 27, 27, 36, 36, 33, 36, 33, 64, 42, 42, 42, 48, 38, 42, 42, 48, 46, 54, 46, 54, 54, 50, 49, 64, 50, 54, 52, 54, 55, 72, 63, 72, 63, 63, 62, 72, 62, 63, 81, 128, 66, 81, 69, 81, 70, 81, 74, 96 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A001222(a(n)) = A001222(n) + 1;

a(2^k) = 2^(k+1).

a(A076156(n)) = A076156(n)+1. - Reinhard Zumkeller, Feb 01 2008

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..10000

MATHEMATICA

lng[n_]:=Module[{x=n+1, pon=PrimeOmega[n]}, While[PrimeOmega[x]-pon!=1, x++]; x]; Array[lng, 80] (* Harvey P. Dale, Nov 09 2011 *)

PROG

(Haskell)

a079890 n = head [x | x <- [n + 1 ..], a001222 x == 1 + a001222 n]

-- Reinhard Zumkeller, Aug 29 2013

CROSSREFS

Cf. A079891, A079892.

Cf. A165712.

Sequence in context: A005884 A229913 A285326 * A223592 A180444 A065608

Adjacent sequences:  A079887 A079888 A079889 * A079891 A079892 A079893

KEYWORD

nonn,nice

AUTHOR

Reinhard Zumkeller, Jan 14 2003

STATUS

approved

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Last modified April 4 06:59 EDT 2020. Contains 333213 sequences. (Running on oeis4.)