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A328497
Terms of A082180 that are not squares or cubes of primes.
3
418, 27173, 2001341, 16024189487
OFFSET
1,1
COMMENTS
Complement of A168363 in A082180.
Are there any other terms like 418 that are not in A228562?
No other terms below 2*10^10. - Max Alekseyev, Dec 15 2023
MATHEMATICA
Select[Range[30000], CompositeQ[#] && Not[IntegerQ[Sqrt[#]]] && Not[IntegerQ[#^(1/3)]] && Mod[Binomial[2*#, #], #] == 2 &] (* Vaclav Kotesovec, Oct 17 2019 *)
PROG
(PARI) forcomposite(c=1, , if(!setintersect(Set(isprimepower(c)), [2, 3]), if(Mod(binomial(2*c, c), c)==2, print1(c, ", "))))
CROSSREFS
The odd terms form A228562.
Sequence in context: A224557 A080467 A292422 * A138062 A350781 A097233
KEYWORD
nonn,hard,more
AUTHOR
Felix Fröhlich, Oct 17 2019
EXTENSIONS
a(4) from Max Alekseyev, Dec 15 2023
STATUS
approved