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Difference between lcm(1,..,n) and the smallest prime > lcm(1,...,n) + 1, where n runs over A000961, lcm(n) runs through A051451.
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%I #8 Nov 18 2015 17:06:03

%S 3,5,5,7,11,13,11,13,31,23,19,37,41,29,31,43,53,41,53,79,59,97,59,61,

%T 113,97,179,73,73,97,103,101,109,101,229,109,139,113,227,131,191,163,

%U 139,199,151,139,181,223,229,367,239,499,251,509,251,227,373,281,233

%N Difference between lcm(1,..,n) and the smallest prime > lcm(1,...,n) + 1, where n runs over A000961, lcm(n) runs through A051451.

%C Analogous to Fortunate numbers and like them so far proved to be primes. This holds for x<=421: if Q is the first follower prime, then Q(421)-lcm(1,...421) = 557. For first some cases when 1+LCM is also a prime, the 2nd primes give 3,5,5,7,11,11,.. deviations, i.e. give primes.

%o (PARI) N=1; for(n=2,1e3, if(isprimepower(n,&p), N*=p; print1(nextprime(N+2)-N", "))) \\ _Charles R Greathouse IV_, Nov 18 2015

%Y Cf. A000961, A003418, A051451, A057019, A037153, A035346, A005235, A054272, A055211, A037155, A045493, A038710 etc

%K nonn

%O 1,1

%A _Labos Elemer_, Nov 14 2000

%E Name corrected by _Charles R Greathouse IV_, Nov 18 2015