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A080102
Smallest prime power in all composite numbers between n-th prime and next prime, a(n)=1 if no such prime power exists.
2
4, 1, 8, 1, 16, 1, 1, 25, 1, 32, 1, 1, 1, 49, 1, 1, 64, 1, 1, 1, 81, 1, 1, 1, 1, 1, 1, 1, 121, 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, 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
OFFSET
2,1
EXAMPLE
There are two prime powers between 32749=A000040(3512) and 32771=A000040(3513): 32761=181^2 and 32768=2^15, therefore a(3512)=32761, A080103(3512)=32768 and A080101(3512)=2.
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jan 28 2003
STATUS
approved