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%I #13 Dec 08 2019 12:25:05
%S 5,44,51,3103,3145,3509,3737,3887,4929,6024,6344,9085,10286,10787,
%T 11725,12035,13052,14314,14816,14839,19071,19662,20513,23779,27950,
%U 28248,35860,36239,41005,45135,48447,50826,52124,53416,59186,64355
%N Numbers k such that the largest prime factor of k is equal to the sum of primes dividing k+1 (with repetition).
%H Amiram Eldar, <a href="/A071861/b071861.txt">Table of n, a(n) for n = 1..10000</a>
%e 3145 is a term because 3145 = 5*17*37 and sopfr(3146) = 2+11+11+13 = 37.
%t seq = {}; gpfPrev = 0; Do[sopfr = Plus @@ Times @@@ (f = FactorInteger[n]); If[sopfr == gpfPrev, AppendTo[seq, n - 1]]; gpfPrev = f[[-1, 1]], {n, 2, 65000}]; seq (* _Amiram Eldar_, Dec 08 2019 *)
%Y Cf. A001414, A006530.
%K nonn
%O 1,1
%A _Jason Earls_, Jun 09 2002
%E Offset corrected by _Amiram Eldar_, Dec 08 2019