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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
 2, 3, 139, 557, 3821, 53609, 179659, 7190917, 3599100, 16687573, 20394197, 101439558 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Corresponding values of m are: 1,2,34,102,530,5462,16309,488739,3599100,308495917,20394197,101439558 Corresponding values of k are: 1,2,4,4,5,4,5,4,5,4,5,5 A023514(i=m,..,m+n-1) are of the same value. LINKS EXAMPLE a(2)=3, because {p(2),p(3)}={3,5}, and {4,6}={2^2,2*3}, k=2; 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. CROSSREFS Cf. A000040, A023514. Sequence in context: A066908 A057738 A234999 * A042073 A124236 A115231 Adjacent sequences:  A254784 A254785 A254786 * A254788 A254789 A254790 KEYWORD nonn AUTHOR Zak Seidov, Feb 15 2015 STATUS approved

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Last modified December 10 23:33 EST 2018. Contains 318049 sequences. (Running on oeis4.)