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A254787 a(n)= least initial term of n consecutive primes {p(m),..,p(m+n-1)} such that all numbers {1+p(m),..,1+p(m+n-1)} are a product of the same number k primes, where p(m) is m-th prime A000040(m). 1

%I #19 Feb 17 2015 00:22:08

%S 2,3,139,557,3821,53609,179659,7190917,3599100,16687573,20394197,

%T 101439558

%N a(n)= least initial term of n consecutive primes {p(m),..,p(m+n-1)} such that all numbers {1+p(m),..,1+p(m+n-1)} are a product of the same number k primes, where p(m) is m-th prime A000040(m).

%C Corresponding values of m are: 1,2,34,102,530,5462,16309,488739,3599100,308495917,20394197,101439558

%C Corresponding values of k are: 1,2,4,4,5,4,5,4,5,4,5,5

%C A023514(i=m,..,m+n-1) are of the same value.

%e a(2)=3, because {p(2),p(3)}={3,5}, and {4,6}={2^2,2*3}, k=2;

%e a(3)=139, because {p(34),p(35),p(36)}={139,149,151}, and {140,150,152}={2^2*5*7,2*3*5^2,2^3*19}, k=4.

%Y Cf. A000040, A023514.

%K nonn

%O 1,1

%A _Zak Seidov_, Feb 15 2015

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Last modified August 19 18:08 EDT 2024. Contains 375310 sequences. (Running on oeis4.)