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A078322 a(n) = rad(n*rad(n)+1), where rad = A007947 (squarefree kernel). 4

%I #24 Nov 12 2022 19:50:04

%S 2,5,10,3,26,37,10,17,14,101,122,73,170,197,226,33,290,109,362,201,

%T 442,485,530,145,42,677,82,393,842,901,962,65,1090,1157,1226,217,1370,

%U 85,1522,401,58,1765,370,969,26,2117,2210,17,86,501,2602,1353,2810,65

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

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

%H Reinhard Zumkeller, <a href="/A078322/b078322.txt">Table of n, a(n) for n = 1..10000</a>

%e 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.

%p rad:= n-> mul(i, i=numtheory[factorset](n)):

%p a:= n-> rad(n*rad(n)+1):

%p seq(a(n), n=1..70); # _Alois P. Heinz_, May 04 2017

%t rad[n_] := Times @@ FactorInteger[n][[All, 1]]; Table[ rad[n*rad[n] + 1], {n, 1, 54}] (* _Jean-François Alcover_, Dec 03 2012 *)

%o (Haskell)

%o a078322 = a007947 . a078310

%o -- _Reinhard Zumkeller_, Oct 19 2011

%o (PARI) rad(n)=vecprod(factor(n)[,1])

%o a(n)=rad(n*rad(n)+1) \\ _Charles R Greathouse IV_, Jul 09 2013

%Y Cf. A007947, A078310, A078325.

%K nonn,nice

%O 1,1

%A _Reinhard Zumkeller_, Nov 23 2002

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Last modified August 1 08:32 EDT 2024. Contains 374811 sequences. (Running on oeis4.)