A078322 a(n) = rad(n*rad(n)+1), where rad = A007947 (squarefree kernel).

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

Author

Reinhard Zumkeller, Nov 23 2002

Keywords

• nonn
• nice

Comments

a(n) = A007947(A078310(n)).

Examples

			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.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A007947, A078310, A078325.

Programs

Haskell

a078322 = a007947 . a078310
-- Reinhard Zumkeller, Oct 19 2011

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 *)

PARI

rad(n)=vecprod(factor(n)[,1])
a(n)=rad(n*rad(n)+1) \\ Charles R Greathouse IV, Jul 09 2013