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A045983
Numbers k such that n or more consecutive integers starting at k have the same number of distinct prime divisors.
17
1, 2, 2, 2, 54, 91, 141, 141, 44360, 48919, 218972, 526095, 526095, 526095, 17233173, 127890362, 29138958036, 118968284928, 118968284928, 585927201062, 585927201062, 585927201062, 585927201062
OFFSET
1,2
COMMENTS
a(n) = smallest number k such that the n numbers from k through n+k-1 have the same number of prime divisors.
a(24) > 10^12. - Donovan Johnson, Mar 29 2013
EXAMPLE
a(5) = 54 as 54, 55, 56, 57, 58 all have 2 prime divisors.
PROG
(PARI) v=vector(16); n=0; c1=0; for(k=1, 127890377, c2=omega(k); if(c1==c2, n++; if(v[n]==0, v[n]=k-n+1; print(n " " v[n])), n=1; c1=c2)) /* Donovan Johnson, Mar 29 2013 */
CROSSREFS
KEYWORD
nonn
EXTENSIONS
a(18)-a(23) from Donovan Johnson, Mar 29 2013
STATUS
approved