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A244378
Numbers k such that 1 + k + k^3 + k^5 + k^7 + k^9 + ... + k^17 is prime.
2
2, 12, 34, 50, 72, 104, 172, 180, 198, 202, 240, 252, 254, 272, 300, 338, 348, 374, 494, 498, 504, 578, 640, 648, 652, 702, 728, 804, 832, 848, 892, 950, 1002, 1040, 1060, 1070, 1134, 1158, 1184, 1364, 1378, 1464, 1564, 1598, 1608, 1624, 1630, 1678, 1688, 1704, 1734
OFFSET
1,1
LINKS
MATHEMATICA
Select[Range[7000], PrimeQ[Total[#^Range[1, 17, 2]] + 1] &]
PROG
(Magma) [n: n in [0..2500] | IsPrime(s) where s is 1+&+[n^i: i in [1..17 by 2]]];
(PARI) isok(n) = isprime(1 + n + n^3 + n^5 + n^7 + n^9 + n^11 + n^13 + n^15 + n^17); \\ Michel Marcus, Jun 27 2014
(Sage)
i, n = var('i, n')
[n for n in (1..2000) if is_prime(1+(n^(2*i+1)).sum(i, 0, 8))] # Bruno Berselli, Jun 27 2014
CROSSREFS
Cf. similar sequences listed in A244376.
Sequence in context: A242709 A055707 A055699 * A062094 A334838 A200543
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jun 27 2014
STATUS
approved