OFFSET
1,1
COMMENTS
The next term, if it exists, is bigger than 2^64.
Conjecture: the sequence is finite. - Alex Ratushnyak, Feb 03 2020
LINKS
Alex Ratushnyak, C program
EXAMPLE
9 = 8 + 1.
25 = 16 + 9.
81 = 32 + 49.
125 = 121 + 4.
512 = 169 + 343.
5041 = 128 + 4913.
MATHEMATICA
nn = 10000; p = Sort[Flatten[Table[Prime[n]^i, {n, PrimePi[Sqrt[nn]]}, {i, 2, Log[Prime[n], nn]}]]]; p = Join[{1}, p]; t = Union[Select[Flatten[Table[p[[i]] + p[[j]], {i, Length[p] - 1}, {j, i + 1, Length[p]}]], # <= nn &]]; Intersection[p, t] (* T. D. Noe, Apr 29 2013 *)
PROG
(C) see link.
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Alex Ratushnyak, Apr 28 2013
STATUS
approved