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A077066
Squarefree kernel of prime(n) + 1.
4
3, 2, 6, 2, 6, 14, 6, 10, 6, 30, 2, 38, 42, 22, 6, 6, 30, 62, 34, 6, 74, 10, 42, 30, 14, 102, 26, 6, 110, 114, 2, 66, 138, 70, 30, 38, 158, 82, 42, 174, 30, 182, 6, 194, 66, 10, 106, 14, 114, 230, 78, 30, 22, 42, 258, 66, 30, 34, 278, 282, 142, 42, 154, 78, 314, 318, 166
OFFSET
1,1
COMMENTS
a(A077067(n)) = A077067(n).
LINKS
FORMULA
a(n) = A007947(A008864(n)).
EXAMPLE
a(25) = rad(prime(25)+1) = rad(97+1) = rad(2*7^2) = 14.
PROG
(PARI) a(n)=my(f=factor(prime(n)+1)[, 1]); prod(i=1, #f, f[i]) \\ Charles R Greathouse IV, Aug 21 2013
(Haskell)
a077066 = a007947 . a008864 -- Reinhard Zumkeller, Sep 04 2013
CROSSREFS
Cf. A077063.
Sequence in context: A129628 A245691 A071044 * A324890 A180240 A065228
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 23 2002
STATUS
approved