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 A284646 #9 Apr 03 2017 20:38:53
%S A284646 2,17,26,37,50,65,82,101,126,145,170,197,217,226,257,325,344,362,401,
%T A284646 442,485,512,513,577,626,677,730,785,901,962,1001,1025,1090,1157,1297,
%U A284646 1445,1522,1601,1682,1729,1765,1850,1937,2026,2117,2198,2305,2402,2501,2602
%N A284646 Variation on Leyland numbers: k = x'^y + y'^x, where x' and y' are the arithmetic derivative of x and y.
%C A284646 Another similar variation on Leyland numbers is k = x^y' + y^x' that leads to A014091.
%e A284646 2' = 1, 4' = 4, 1^4 + 4^2 = 1 + 16 = 17.
%p A284646 with(numtheory): N:= 10^5: A:={}: for x from 2 to floor(N^(1/2)) do
%p A284646 for y from 2 do yd:=y*add(op(2,p)/op(1,p),p=ifactors(y)[2]); xd:=x*add(op(2,p)/op(1,p),p=ifactors(x)[2]); a:= xd^y + yd^x;
%p A284646 if a>N then break fi; A:=A union {a}; od; od; sort([op(A)]);
%p A284646 # based on _Robert Israel_ code in A076980.
%Y A284646 Cf. A014091, A076980.
%K A284646 nonn
%O A284646 1,1
%A A284646 _Paolo P. Lava_, Mar 31 2017