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%I #14 Jan 01 2019 17:07:50
%S 1,1,1,1,1,1,1,1,13,13,23,23,23,17,19,19,1,1,1,1,1,1,1,1,31,31,1,1,1,
%T 1,1,1,1,1,43,43,43,43,47,47,59,59,59,59,1,1,59,59,59,59,61,61,61,61,
%U 61,61,113,113,1,1,1,97,97,97,73,73,73,73,73,73,97
%N a(n) = Min { { smallest prime > k } - k, k - { largest prime < k } }, where k = lcm(1..n) = A003418(n).
%p [seq( min( nextprime(A003418(n))-A003418(n), A003418(n)-prevprime(A003418(n)) ), n=3..100)];
%t Min[NextPrime[#]-#,#-NextPrime[#,-1]]&/@Table[LCM@@Range[n],{n,80}] (* _Harvey P. Dale_, Jan 01 2019 *)
%o (PARI) a(n) = my(lcn = lcm([1..n])); min(nextprime(lcn+1)-lcn, lcn-precprime(lcn-1)); \\ _Michel Marcus_, Mar 29 2018
%Y Cf. A003418, A060357, A060358, A060359, A060360, A060361.
%K nonn
%O 3,9
%A _N. J. A. Sloane_, Apr 01 2001
%E Definition corrected by _Jon E. Schoenfield_, Mar 18 2018