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A108249 Consider primes p and q such that p = 3^k + 20 and q = 3^(k+1) + 20 for some k; sequence gives values of p. 1
23, 29, 47, 101, 2207, 59069 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..6.

EXAMPLE

3^1 + 20 = 23, 3^2 + 20 = 29.

PROG

(PARI) g(m, n, b) = { for(x=0, n, y=m+b^x+b%2; z=m+b^(x+1)+b%2; if(isprime(y)&isprime(z), print1(y", ") ) ) }

CROSSREFS

Cf. A108258.

Sequence in context: A108111 A085713 A102904 * A232725 A045120 A174260

Adjacent sequences:  A108246 A108247 A108248 * A108250 A108251 A108252

KEYWORD

nonn

AUTHOR

Cino Hilliard, Jun 29 2005

STATUS

approved

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Last modified April 18 06:48 EDT 2019. Contains 322209 sequences. (Running on oeis4.)