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.
%I A195334 #16 Apr 13 2019 11:25:24
%S A195334 4,8,18,32,50,128,578,1458,3362,4802,6962,8192,10082,15842,20402,
%T A195334 31250,34322,55778,57122,59858,131072,167042,171698,293378,524288,
%U A195334 559682,916658,982802,1062882,1104098,1158242,1195058,1367858,1407842,1414562,1468898,1659842
%N A195334 Numbers the sum of whose even divisors is 2 times a prime.
%C A195334 a(n) is of the form m^2 or 2*m^2.
%C A195334 (See A195268, which has similar properties.)
%F A195334 Conjecture: a(n) = 2*A023194(n). - _R. J. Mathar_, Sep 15 2011
%e A195334 The divisors of 18 are {1, 2, 3, 6, 9, 18}, and half the sum of the even divisors is (2 + 6 + 18)/2 = 26/2 = 13, which is prime. Hence 18 is in the sequence.
%p A195334 A146076 := proc(n) a :=0 ; for d in numtheory[divisors](n) do if type(d,'even') then a := a+d; end if; end do; a; end proc:
%p A195334 isA195334 := proc(n) isprime(A146076(n)/2) ; end proc:
%p A195334 for n from 1 do if isA195334(n) then print(n); end if; end do: # _R. J. Mathar_, Sep 15 2011
%t A195334 Select[Range[2000000],PrimeQ[Total[Select[Divisors[#],EvenQ]]/2]&] (* _Harvey P. Dale_, Mar 07 2012 *)
%Y A195334 Cf. A146076, A195268.
%K A195334 nonn
%O A195334 1,1
%A A195334 _Michel Lagneau_, Sep 15 2011