OFFSET
1,1
COMMENTS
Although it is easy to produce many terms of this sequence, it is nontrivial to check efficiently whether a very large number is of this form.
EXAMPLE
The sequence starts with 1^6 + 1^7, 2^6 + 1^7, 1^6 + 2^7, 2^6 + 2^7, 3^6 + 1^7, 3^6 + 2^7, ...
MATHEMATICA
With[{nn=40}, Take[Union[First[#]^6 + Last[#]^7&/@Tuples[Range[nn], 2]], nn]] (* Vincenzo Librandi, Apr 25 2018 *)
PROG
(PARI) is(n, k=6, m=7)=for(b=1, sqrtnint(n-1, m), ispower(n-b^m, n)&&return(b)) \\ Returns b > 0 if n is in the sequence, else 0.
A303376_vec(L=10^5, k=6, m=7, S=List())={for(a=1, sqrtnint(L-1, m), for(b=1, sqrtnint(L-a^m, k), listput(S, a^m+b^k))); Set(S)} \\ all terms up to limit L
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
M. F. Hasler, Apr 22 2018
STATUS
approved