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A275509 First occurrence of a run of exactly n consecutive integers with an odd number of prime factors. 0
5, 2, 11, 17, 41, 27, 170, 279, 428, 8825, 5879, 27937, 19453, 13871, 41233, 171707, 1100826, 1004646, 1633357, 5460156, 11902755, 49390927, 21627159, 38821328, 41983357, 619535061, 259681234, 1250565732, 799932281, 4168699147, 867086432, 2487208142, 179376463 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..33.

EXAMPLE

a(3) = 11 because 11 begins the first occurrence of a run of exactly 3 consecutive integers with an odd number of prime factors, i.e., 11, 12 = 2 * 2 * 3, 13.

PROG

(PARI) v=vector(100); last=0; for(n=1, 1e10, if(bigomega(n)%2==0, t=n-last-1; if(t && v[t]==0, v[t]=n-t; print(t" "n-t)); last=n)) \\ Charles R Greathouse IV, Jul 31 2016

CROSSREFS

Cf. A005408, A066829, A066794.

Sequence in context: A302773 A249369 A065268 * A286142 A286143 A130298

Adjacent sequences:  A275506 A275507 A275508 * A275510 A275511 A275512

KEYWORD

nonn

AUTHOR

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

EXTENSIONS

a(9)-a(33) from Charles R Greathouse IV, Jul 31 2016

STATUS

approved

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Last modified November 15 01:15 EST 2019. Contains 329142 sequences. (Running on oeis4.)