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A070229 Next m>n such that m is divisible by lpf(n), lpf=A006530 largest prime factor. 13

%I

%S 2,4,6,6,10,9,14,10,12,15,22,15,26,21,20,18,34,21,38,25,28,33,46,27,

%T 30,39,30,35,58,35,62,34,44,51,42,39,74,57,52,45,82,49,86,55,50,69,94,

%U 51,56,55,68,65,106,57,66,63,76,87,118,65,122

%N Next m>n such that m is divisible by lpf(n), lpf=A006530 largest prime factor.

%C Or, for n>1, n + (largest prime divisor of n). [Anne Robinson, daughter of _Herman P. Robinson_, Oct 08 1981]

%H Reinhard Zumkeller, <a href="/A070229/b070229.txt">Table of n, a(n) for n = 1..10000</a>

%H H. P. Robinson, <a href="/A006530/a006530.pdf">Letter to N. J. A. Sloane, Oct 1981</a>

%F a(n) = (n/lpf(n)+1)*lpf(n).

%F a(n) = n+lpf(n) where lpf=A006530 largest prime factor. For example, a(14)=14+7=21 (instead of ((14/7)+1))*7). - Philippe Lallouet (philip.lallouet(AT)wanadoo.fr), Jun 14 2007

%t Table[n + Last@(First/@FactorInteger[n]), {n, 70}] (* _Vladimir Joseph Stephan Orlovsky_, Apr 08 2011 *)

%o (Haskell)

%o a070229 n = n + a006530 n

%o -- _Reinhard Zumkeller_, Nov 08 2015, Nov 14 2011

%o (PARI) vector(100, n, if(n>1, vecmax(factor(n)[, 1]), 1) + n) \\ _Altug Alkan_, Nov 13 2015

%Y Cf. A036441.

%Y Cf. A006530, A061228, A256393.

%Y Iterations: A076271 (start=1), A036441 (start=2), A123581 (start=3).

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, May 07 2002

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Last modified October 16 17:49 EDT 2019. Contains 328102 sequences. (Running on oeis4.)