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%I #7 Oct 12 2013 15:24:50
%S 4,3,9,4,16,9,11,27,5,32,19,7,23,49,29,5,64,23,9,37,81,43,47,49,17,53,
%T 27,37,125,128,67,23,73,25,31,81,83,169,89,9,61,64,97,11,103,109,113,
%U 19,29,79,16,243,256,131,89,27,137,139,47,289
%N Largest prime (or prime power) that divides any number between the primes p(n) and p(n+1).
%e a(4) = 9 because, of the numbers between 7 (= p(4)) and 11 (= p(5)), 9 has the largest prime, or prime-to-a-power, divisor (namely, itself). a(13) = 7 because only 42 lies between 41 (= p(13)) and 43 (= p(14)) and its largest prime divisor is 7.
%o (PARI) a(n) = {ppmax = 1; for (i = prime(n)+1, prime(n+1)-1, f = factor(i); for (j = 1, #f~, ppmax = max(ppmax, f[j,1]^f[j, 2]););); ppmax;} \\ _Michel Marcus_, Aug 25 2013
%K easy,nonn
%O 2,1
%A _Greg Huber_, Feb 10 2006
%E More terms from Joseph Pedersen (jmp456(AT)psu.edu), Apr 27 2006
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