%I #7 Mar 22 2020 12:19:10
%S 1,1,2,3,2,4,1,2,3,2,8,12,1,2,2,5,6,6,2,3,6,6,2,2,8,3,4,2,12,2,9,8,18,
%T 2,2,6,4,12,2,3,6,4,2,6,12,8,2,6,2,1,6,8,2,2,14,4,6,2,6,2,3,20,2,12,2,
%U 2,8,14,10,18,8,6,2,2,2,12,12,19,2,6,6,20,2,2,2,8,8,2,2,8,20,12,15,2,4
%N Difference between a nontrivial prime power (A025475) and the previous prime.
%C a(n)=1 only for some powers of 2.
%F a(n) = A025475(n)-prevprime(A025475(n)) = A025475(n)-A049711(A025475(n)).
%e 78125=5^7 follows 78121, the difference is 4.
%Y Cf. A025475, A000961, A001597, A001694, A007917, A007918, A013632, A013633, A049711.
%K nonn
%O 1,3
%A _Labos Elemer_, May 03 2001
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