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%I #9 May 13 2013 01:54:18
%S 2,3,10,5,14,7,78,33,22,11,26,13,114,51,34,17,38,19,290,69,46,23,174,
%T 145,186,87,58,29,62,31,222,185,430,111,74,37,258,123,82,41,86,43,530,
%U 141,94,47,318,265,590,159,106,53,354,295,366,177,118,59,122,61
%N Smallest number k such that the difference between the greatest prime divisor of k and the product of the other distinct prime divisors equals n.
%C a(n) = n+1 if n+1 is prime.
%H Charles R Greathouse IV, <a href="/A182076/b182076.txt">Table of n, a(n) for n = 1..10000</a>
%e a(7) = 78 because the distinct prime divisors of 78 are {2, 3, 13} and 13 - 2*3 = 7.
%p with(numtheory):for n from 1 to 60 do:ii:=0:for k from 2 to 200000 while(ii=0) do:x:=factorset(k):m:=nops(x): s:=product ('x[i] ', 'i'=1..m-1):if s+n = x[m] then printf(`%d, `,k):ii:=1:else fi:od: od:
%o (PARI) a(n)=my(t);for(k=n+1,4<<n,if(issquarefree(k),t=factor(k)[,1];if(t[#t]-k/t[#t]==n,return(k)))) \\ _Charles R Greathouse IV_, Apr 11 2012
%o (PARI) a(n)=my(p=nextprime(n+1));while(!issquarefree(p-n), p=nextprime(p+1));p*(p-n) \\ _Charles R Greathouse IV_, Apr 11 2012
%Y Cf. A001221, A182011.
%K nonn,easy
%O 1,1
%A _Michel Lagneau_, Apr 10 2012
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