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A178227 Lesser of a pair (p,p+4) of cousin primes whose arithmetic mean p+2 is a cube. 1
2146687, 6751267, 50243407, 82312873, 165469147, 170953873, 176558479, 549353257, 1929781123, 3314613769, 5079577957, 5630252137, 6219352717, 6591796873, 7245075373, 10289109373, 11993263567 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

p = n^3 - 2, p and p+4 are "near(est) cube" primes as n^3 -/+ 1 = (n -/+ 1) * (n^2 +/- n + 1)

LINKS

Table of n, a(n) for n=1..17.

EXAMPLE

p=2146687 is a term, as p+2=129^3 and both p=129^3-2 and p+4=129^3+2 are prime.

PROG

(PARI) isok(p) = isprime(p) && (q=nextprime(p+1)) && (q-p==4) && ispower(p+2, 3); \\ Michel Marcus, Nov 27 2016

CROSSREFS

Cf. A046132, A172494, A174370, A176130, A176229.

Sequence in context: A237140 A129477 A235930 * A154709 A184476 A144587

Adjacent sequences:  A178224 A178225 A178226 * A178228 A178229 A178230

KEYWORD

nonn,more

AUTHOR

Ulrich Krug (leuchtfeuer37(AT)gmx.de), May 23 2010

EXTENSIONS

Corrected by D. S. McNeil, Nov 24 2010

STATUS

approved

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Last modified June 25 10:10 EDT 2019. Contains 324351 sequences. (Running on oeis4.)