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A191865 Primes of the form (n-1)^6 + n^5 + (n+1)^4. 1
17, 563, 67559, 758677727, 5639788283, 12519315713, 228317617103, 2215267259747, 2458514680949, 5331791014853, 9754511753219, 11469661520567, 60568409162663, 64329745367417, 148696534573127, 164890314104507, 1843608625927967, 2182930574787737, 5990875533026939 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Sum of three consecutive numbers using exponents 6, 5, and 4 to generate prime numbers from n^6 - 5n^5 + 16n^4 - 16n^3 + 21n^2 - 2n + 2 = (n-1)^6 + n^5 + (n+1)^4.
LINKS
EXAMPLE
2^6 + 3^5 + 4^4 = 563 and 6^6 + 7^5 + 8^4 = 67559 are primes in the sequence.
MAPLE
R:= NULL: count:= 0:
for n from 1 by 2 while count < 100 do
v:= (n-1)^6+n^5+(n+1)^4;
if isprime(v) then count:= count+1; R:= R, v; fi
od:
R; # Robert Israel, Jan 05 2021
MATHEMATICA
lst={}; Do[If[PrimeQ[p=(n-1)^6+n^5+(n+1)^4], AppendTo[lst, p]], {n, 200}]; lst
lst={}; Do[If[PrimeQ[p=n^6-5n^5+16n^4-16n^3+21n^2-2n+2], AppendTo[lst, p]], {n, 200}]; lst
PROG
(PARI) forstep(n=1, 1e3, 2, if(isprime(k=(n-1)^6+n^5+(n+1)^4), print1(k", "))) \\ Charles R Greathouse IV, Jun 19 2011
CROSSREFS
Sequence in context: A197395 A280181 A012069 * A249862 A056771 A041547
KEYWORD
nonn
AUTHOR
Rafael Parra Machio, Jun 18 2011
STATUS
approved

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Last modified June 29 17:26 EDT 2024. Contains 373855 sequences. (Running on oeis4.)