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A275508 First occurrence of a run of exactly n consecutive integers with an even number of prime factors. 0
1, 9, 14, 33, 54, 201, 140, 2170, 213, 4529, 10403, 1934, 35811, 162144, 38405, 414225, 200938, 389409, 1792209, 5606457, 18493931, 30947532, 61190563, 8405437, 203631499, 577699919, 158280474, 68780189, 4082994208, 3944563444 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..30.

EXAMPLE

a(3)=14 because 14 begins the first occurrence of a run of exactly 3 consecutive integers with an even number of prime factors, i.e., 14=2*7, 15=3*5, 16=2*2*2*2.

PROG

(PARI) v=vector(100); last=0; for(n=1, 1e10, if(bigomega(n)%2, t=n-last-1; if(t && v[t]==0, v[t]=n-t; print(t" "n-t)); last=n)) \\ Charles R Greathouse IV, Jul 30 2016

CROSSREFS

Cf. A005843, A066829.

Sequence in context: A229543 A175201 A066793 * A139055 A294030 A079625

Adjacent sequences:  A275505 A275506 A275507 * A275509 A275510 A275511

KEYWORD

nonn

AUTHOR

G. L. Honaker, Jr., Jul 30 2016

EXTENSIONS

a(11)-a(30) from Charles R Greathouse IV, Jul 30 2016

STATUS

approved

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Last modified December 8 17:36 EST 2019. Contains 329865 sequences. (Running on oeis4.)