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First occurrence of a run of exactly n consecutive integers with an odd number of prime factors.
1

%I #13 Aug 01 2016 00:47:11

%S 5,2,11,17,41,27,170,279,428,8825,5879,27937,19453,13871,41233,171707,

%T 1100826,1004646,1633357,5460156,11902755,49390927,21627159,38821328,

%U 41983357,619535061,259681234,1250565732,799932281,4168699147,867086432,2487208142,179376463

%N First occurrence of a run of exactly n consecutive integers with an odd number of prime factors.

%e 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.

%o (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

%Y Cf. A005408, A066829, A066794.

%K nonn

%O 1,1

%A _G. L. Honaker, Jr._, Jul 30 2016

%E a(9)-a(33) from _Charles R Greathouse IV_, Jul 31 2016