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A213811 Numbers k such that k and k^3 are sums of two twin primes. 2
1044, 1200, 2604, 2964, 4056, 4284, 4476, 7164, 7644, 9300, 9864, 10884, 14616, 15180, 20916, 24084, 40716, 51156, 55056, 65436, 66144, 70104, 74676, 92100, 99060, 104580, 105804, 163944, 164700, 165780, 209604, 218400, 219660, 222540, 226656, 257040, 281676 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are multiples of 12.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Harvey P. Dale)

FORMULA

k/2 +/-1 and also (k^3)/2 +/- 1 are twin primes.

EXAMPLE

1044=521+523, 1044^3=1137893184=568946591+568946593.

MATHEMATICA

sttpQ[n_]:=Module[{x=(n-2)/2}, AllTrue[{x, x+2}, PrimeQ]]; Select[Range[ 12, 300000, 12], sttpQ[#]&&sttpQ[#^3]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jul 25 2017 *)

PROG

(PARI) isok(n) = !(n % 2) && isprime(n/2-1) && isprime(n/2+1) && isprime(n^3/2-1) && isprime(n^3/2+1); \\ Michel Marcus, Oct 19 2013

CROSSREFS

Cf. A001043, A074924, A213784, A213789.

Sequence in context: A183742 A252618 A231112 * A260205 A224604 A045027

Adjacent sequences:  A213808 A213809 A213810 * A213812 A213813 A213814

KEYWORD

nonn

AUTHOR

Zak Seidov, Jun 20 2012

STATUS

approved

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Last modified June 13 11:17 EDT 2021. Contains 344990 sequences. (Running on oeis4.)