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A076764 n such that Omega(n-1) < Omega(n) < Omega(n+1), where Omega(m) = the number of prime factors of m, counting multiplicity. 1
62, 63, 74, 188, 194, 195, 207, 242, 255, 275, 278, 279, 314, 363, 374, 398, 399, 404, 422, 423, 455, 458, 483, 494, 495, 524, 539, 614, 615, 662, 663, 674, 692, 728, 734, 735, 747, 758, 759, 764, 782, 783, 854, 867, 890, 927, 935, 975, 998, 999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

Omega(61) = 1 < Omega(62) = 2 < Omega(63) = 3, so 62 is a 1-apex of Omega.

MAPLE

Res:= NULL: a:= numtheory:-bigomega(1): b:= numtheory:-bigomega(2):

for n from 3 to 1001 do

  c:= numtheory:-bigomega(n);

  if a < b and b < c then Res:= Res, n-1 fi;

  a:= b; b:= c;

od:

Res; # Robert Israel, Oct 28 2018

MATHEMATICA

Select[Range[3, 10^3], Omega[ # - 1] < Omega[ # ] < Omega[ # + 1] &]

Flatten[Position[Partition[PrimeOmega[Range[1000]], 3, 1], _?(Min[ Differences[ #]]>0&), {1}, Heads->False]]+1 (* Harvey P. Dale, Nov 28 2015 *)

CROSSREFS

Cf. A001222, A097619.

Sequence in context: A296766 A003635 A188631 * A214251 A031058 A084801

Adjacent sequences:  A076761 A076762 A076763 * A076765 A076766 A076767

KEYWORD

nonn

AUTHOR

Joseph L. Pe, Nov 13 2002

EXTENSIONS

Edited by Robert Israel, Oct 28 2018

STATUS

approved

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Last modified August 11 00:32 EDT 2020. Contains 336403 sequences. (Running on oeis4.)