cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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

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%I A070229 #35 Aug 20 2024 03:11:08
%S A070229 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 A070229 30,39,30,35,58,35,62,34,44,51,42,39,74,57,52,45,82,49,86,55,50,69,94,
%U A070229 51,56,55,68,65,106,57,66,63,76,87,118,65,122
%N A070229 Next m>n such that m is divisible by lpf(n), lpf=A006530 largest prime factor.
%C A070229 Or, for n>1, n + (largest prime divisor of n). [Anne Robinson, daughter of _Herman P. Robinson_, Oct 08 1981]
%H A070229 Reinhard Zumkeller, <a href="/A070229/b070229.txt">Table of n, a(n) for n = 1..10000</a>
%H A070229 H. P. Robinson, <a href="/A006530/a006530.pdf">Letter to N. J. A. Sloane, Oct 1981</a>
%F A070229 a(n) = (n/lpf(n)+1)*lpf(n).
%F A070229 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 A070229 Table[n + Last@(First/@FactorInteger[n]), {n, 70}] (* _Vladimir Joseph Stephan Orlovsky_, Apr 08 2011 *)
%o A070229 (Haskell)
%o A070229 a070229 n = n + a006530 n
%o A070229 -- _Reinhard Zumkeller_, Nov 08 2015, Nov 14 2011
%o A070229 (PARI) vector(100, n, if(n>1, vecmax(factor(n)[, 1]), 1) + n) \\ _Altug Alkan_, Nov 13 2015
%Y A070229 Cf. A036441.
%Y A070229 Cf. A006530, A061228, A256393.
%Y A070229 Iterations: A076271 (start=1), A036441 (start=2), A123581 (start=3).
%K A070229 nonn,easy
%O A070229 1,1
%A A070229 _Reinhard Zumkeller_, May 07 2002