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Greatest prime power in all composite numbers between n-th prime and next prime, a(n)=1 if no such prime power exists.
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%I #4 Mar 30 2012 18:50:31

%S 4,1,9,1,16,1,1,27,1,32,1,1,1,49,1,1,64,1,1,1,81,1,1,1,1,1,1,1,125,

%T 128,1,1,1,1,1,1,1,169,1,1,1,1,1,1,1,1,1,1,1,1,1,243,256,1,1,1,1,1,1,

%U 289,1,1,1,1,1,1,343,1,1,1,361,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1

%N Greatest prime power in all composite numbers between n-th prime and next prime, a(n)=1 if no such prime power exists.

%e There are two prime powers between 7=A000040(4) and 11=A000040(5): 8=2^3 and 9=3^2, therefore a(4)=9, A080102(4)=8 and A080101(4)=2.

%Y Cf. A080101, A080102, A025475, A000961.

%K nonn

%O 2,1

%A _Reinhard Zumkeller_, Jan 28 2003