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 A180852 #14 Nov 20 2024 12:16:14
%S A180852 2,9,18,5618,7744,10000,28561,30258,34322,40000,46225,165649,200978,
%T A180852 249218,258064,310472,370881,393129,425042,438244,542882,595984,
%U A180852 865928,916658,971618,1932578,2477476,2558322,3367225,3737378,3770258,3964081
%N A180852 Numbers n such that the sum_i (d_i^i) of the i-th powers of their sorted divisors d_1< d_2<...< n is prime.
%H A180852 Robert G. Wilson v, <a href="/A180852/b180852.txt">Table of n, a(n) for n = 1..100</a>.
%e A180852 9 is a term since the divisors of 9 are [1, 3, 9] and 1^1+3^2+9^3 = 739, a prime.
%p A180852 isA180852 := proc(n) d := sort(convert(numtheory[divisors](n),list)) ; add( op(i,d)^i,i=1..nops(d)) ; isprime(%) ; end proc:
%p A180852 for n from 1 do if isA180852(n) then printf("%d,\n",n) ; end if; end do: # _R. J. Mathar_, Sep 23 2010
%t A180852 fQ[n_] := Block[{d = Divisors@ n}, PrimeQ[ Plus @@ (d^Range@ Length@ d)]]; Select[ Range@ 4000000, fQ] (* _Robert G. Wilson v_, Sep 25 2010 *)
%t A180852 Select[Range[4*10^6],PrimeQ[Total[Divisors[#]^Range[DivisorSigma[0,#]]]]&] (* _Harvey P. Dale_, Nov 20 2024 *)
%K A180852 nonn
%O A180852 1,1
%A A180852 _Jason Earls_, Sep 21 2010
%E A180852 Slightly more precise definition by _R. J. Mathar_, Sep 23 2010
%E A180852 a(27) onwards from _Robert G. Wilson v_, Sep 25 2010