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A106066 Primes p such that 1*p+20 and 20*p+1 are primes. 2
3, 23, 41, 47, 53, 59, 107, 131, 137, 173, 179, 191, 251, 263, 293, 311, 443, 467, 503, 599, 641, 971, 977, 1013, 1049, 1151, 1277, 1301, 1307, 1409, 1427, 1433, 1451, 1559, 1607, 1721, 1913, 1973, 1979, 2069, 2111, 2141, 2267, 2417, 2693, 2729, 2777, 2999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..48.

MATHEMATICA

Select[Prime[Range[220]], PrimeQ[20#+1]&&PrimeQ[1#+20]&]

PROG

(MAGMA) [p: p in PrimesUpTo(10000)| IsPrime(p+20) and IsPrime(20*p+1)] // Vincenzo Librandi, Nov 13 2010

CROSSREFS

Sequence in context: A245623 A106892 A116893 * A281551 A167216 A309935

Adjacent sequences:  A106063 A106064 A106065 * A106067 A106068 A106069

KEYWORD

nonn

AUTHOR

Zak Seidov, May 07 2005

EXTENSIONS

More terms from Vincenzo Librandi, Apr 01 2010

STATUS

approved

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Last modified August 17 12:30 EDT 2022. Contains 356189 sequences. (Running on oeis4.)