A095365 - OEIS

A095365

Primes p such that f(q) < f(p) for all primes q < p, where f(p) = lcm(2-1, 3-1, 5-1, 7-1, 11-1, ..., p-1).

%I #6 Mar 17 2018 23:37:33

%S 2,3,5,7,11,17,19,23,29,47,53,59,83,97,101,103,107,109,149,163,167,

%T 173,179,191,193,197,227,251,257,263,269,283,293,311,317,347,359,367,

%U 383,389,467,479,487,503,509,557,563,569,587,607,619,643,653,677,709,719

%N Primes p such that f(q) < f(p) for all primes q < p, where f(p) = lcm(2-1, 3-1, 5-1, 7-1, 11-1, ..., p-1).

%C A058255 gives the values of f(p) for the primes p in this sequence. The odd primes in this sequence seem to be the only values appearing in A095366.

%e 13 is not a member of this sequence because f(11) = f(13) = 60.

%t nn=200; lst={}; lcm=1; Do[p=Prime[i]; newLCM=LCM[lcm, p-1]; If[newLCM>lcm, lcm=newLCM; AppendTo[lst, p]], {i, 2, nn}]; lst

%K nonn

%O 1,1

%A _T. D. Noe_, Jun 03 2004