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A171525
Numerator of (n-th noncomposite/n).
2
1, 1, 1, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227
OFFSET
1,4
COMMENTS
Numerator of (A008578(n)/n). a(1)= a(2) = a(3) = 1, a(n) = A008578(n) = A000040(n-1) for n >= 4.
PROG
(PARI) a(n)=if(n>3, prime(n-1), 1) \\ Charles R Greathouse IV, Aug 22 2011
CROSSREFS
Sequence in context: A276378 A243292 A271116 * A140475 A171577 A215848
KEYWORD
nonn,easy
AUTHOR
Jaroslav Krizek, Dec 11 2009
STATUS
approved