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A219048 Numbers n such that 3^n + 32 is prime. 16
2, 3, 4, 6, 23, 24, 38, 164, 172, 176, 207, 216, 251, 272, 424, 1112, 1318, 2072, 2664, 3143, 4704, 5236, 9526, 13064, 13523, 27111, 35931, 37504, 47542, 128656, 181551 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(32) > 2*10^5. - Robert Price, Nov 15 2013

LINKS

Table of n, a(n) for n=1..31.

EXAMPLE

For n=2, a(2)=3^2+32=41 and 41 is prime. Hence n=2 is included in the sequence.

MATHEMATICA

Do[If[PrimeQ[3^n + 32], Print[n]], {n, 10000}]

PROG

(PARI) is(n)=isprime(3^n+32) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Cf. Sequences of numbers n such that 3^n + m is prime:

  (m = 2) A051783, (m = -2) A014224, (m = 4) A058958, (m = -4) A058959,

  (m = 8) A217136, (m = -8) A217135, (m = 10) A217137, (m = -10) A217347,

  (m = 14) A219035, (m = -14) A219038, (m = 16) A205647, (m = -16) A219039,

  (m = 20) A219040, (m = -20) A219041, (m = 22) A219042, (m = -22) A219043,

  (m = 26) A219044, (m = -26) A219045, (m = 28) A219046, (m = -28) A219047,

  (m = 32) A219048, (m = -32) A219049, (m = 34) A219050, (m = -34) A219051. Note that if m is a multiple of 3, 3^n + m is also a multiple of 3 (for n greater than 0), and as such isn't prime.

Sequence in context: A217351 A274238 A115035 * A329577 A217442 A065199

Adjacent sequences:  A219045 A219046 A219047 * A219049 A219050 A219051

KEYWORD

nonn,more

AUTHOR

Nicolas M. Perrault, Nov 10 2012

EXTENSIONS

a(23)-a(31) from Robert Price, Nov 15 2013

STATUS

approved

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Last modified September 20 07:46 EDT 2020. Contains 337264 sequences. (Running on oeis4.)