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A111389 Numbers n such that p(3n) is prime, where p(n) is the number of partitions of n. 14
1, 2, 12, 44, 56, 62, 72, 122, 139, 166, 175, 182, 245, 251, 275, 362, 432, 526, 712, 831, 834, 836, 856, 909, 957, 1009, 1056, 1114, 1554, 2266, 2486, 2816, 3967, 4340, 5416, 6092, 6837, 6959, 7215, 7255, 7439, 7734, 9655, 10200, 11080, 11324, 11361, 12819 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Max Alekseyev, Table of n, a(n) for n = 1..1669

FORMULA

Elements of A046063 which are == 0 (mod 3) divided by 3

EXAMPLE

If n=72 then p(3n) = 15285151248481 (prime).

MATHEMATICA

Select[ Range[13370], PrimeQ[ PartitionsP[3# ]] &] (* Robert G. Wilson v *)

PROG

(PARI) is(n)=isprime(numbpart(3*n)) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Cf. A000041, A046063, A114165, A111389, A111045, A114166, A111036, A114167, A114168, A114169, A114170.

Sequence in context: A301556 A055681 A296682 * A203278 A013704 A025495

Adjacent sequences:  A111386 A111387 A111388 * A111390 A111391 A111392

KEYWORD

nonn

AUTHOR

Parthasarathy Nambi, Nov 09 2005

EXTENSIONS

a(8)-a(48) from Robert G. Wilson v, Nov 11 2005

STATUS

approved

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Last modified July 23 22:20 EDT 2021. Contains 346265 sequences. (Running on oeis4.)