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A078322
a(n) = rad(n*rad(n)+1), where rad = A007947 (squarefree kernel).
4
2, 5, 10, 3, 26, 37, 10, 17, 14, 101, 122, 73, 170, 197, 226, 33, 290, 109, 362, 201, 442, 485, 530, 145, 42, 677, 82, 393, 842, 901, 962, 65, 1090, 1157, 1226, 217, 1370, 85, 1522, 401, 58, 1765, 370, 969, 26, 2117, 2210, 17, 86, 501, 2602, 1353, 2810, 65
OFFSET
1,1
COMMENTS
a(n) = A007947(A078310(n)).
LINKS
EXAMPLE
a(25) = rad(25*rad(25)+1) = rad(25*rad(5^2)+1) = rad(25*5+1) = rad(125+1) = rad(126) = rad(2*3*3*7) = 2*3*7 = 42.
MAPLE
rad:= n-> mul(i, i=numtheory[factorset](n)):
a:= n-> rad(n*rad(n)+1):
seq(a(n), n=1..70); # Alois P. Heinz, May 04 2017
MATHEMATICA
rad[n_] := Times @@ FactorInteger[n][[All, 1]]; Table[ rad[n*rad[n] + 1], {n, 1, 54}] (* Jean-François Alcover, Dec 03 2012 *)
PROG
(Haskell)
a078322 = a007947 . a078310
-- Reinhard Zumkeller, Oct 19 2011
(PARI) rad(n)=vecprod(factor(n)[, 1])
a(n)=rad(n*rad(n)+1) \\ Charles R Greathouse IV, Jul 09 2013
CROSSREFS
KEYWORD
nonn,nice
AUTHOR
Reinhard Zumkeller, Nov 23 2002
STATUS
approved