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A128456
Quotients A128452(p+1)/p for prime p = A000040(n).
7
2, 7, 311, 127, 23, 157, 7563707819165039903, 75368484119, 47, 9629, 311, 25679, 821, 758771382833029, 12409, 71233, 18438666190697, 2443783, 2939291, 71711, 352883, 181113265579, 167, 105199, 3881, 1314520253, 619, 20759, 117503, 1162660843
OFFSET
1,1
COMMENTS
a(n) coincides with A128357(n) from n = 2 up to n = 6.
FORMULA
a(n) = A128452(A000040(n)+1)/A000040(n).
a(n) = A020639(((p+1)^p - 1)/p^2), i.e., the smallest prime factor of ((p+1)^p - 1)/p^2, where p = A000040(n).
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, Mar 05 2007, Mar 09 2007
EXTENSIONS
Terms a(14) onward from Max Alekseyev, May 05 2010
STATUS
approved