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A090711 Primes whose base-11 expansion is a (valid) decimal expansion of a prime. 1
2, 3, 5, 7, 31, 47, 67, 73, 97, 163, 223, 227, 229, 271, 311, 317, 331, 397, 421, 443, 449, 557, 683, 727, 733, 773, 883, 953, 977, 991, 997, 1063, 1109, 1129, 1367, 1373, 1433, 1483, 1607, 1613, 1637, 1657, 1697, 1723, 1783, 1871, 1873, 1879, 2027, 2203, 2269 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A091924 for the sequence whose definition works "the other way round": Actually, the base-11 representation of the terms of this sequence here. - M. F. Hasler, Jan 03 2014

LINKS

Table of n, a(n) for n=1..51.

EXAMPLE

The prime p = 31 is written 29 in base 11, and 29 read in base 10 is again a prime. So 31 is a term.

MATHEMATICA

b11pQ[n_]:=Module[{d=IntegerDigits[n, 11]}, Max[d]<10&&PrimeQ[FromDigits[ d]]]; Select[Prime[Range[400]], b11pQ] (* Harvey P. Dale, Apr 17 2018 *)

PROG

(PARI) is(p, b=10, c=11)=vecmax(d=digits(p, c))<b&&isprime(vector(#d, i, b^(#d-i))*d~)&&isprime(p) \\ - M. F. Hasler, Jan 05 2014

CROSSREFS

Cf. A090712.

Sequence in context: A245064 A052014 A236255 * A067907 A289759 A175611

Adjacent sequences:  A090708 A090709 A090710 * A090712 A090713 A090714

KEYWORD

base,nonn

AUTHOR

Cino Hilliard, Jan 18 2004

EXTENSIONS

Edited by N. J. A. Sloane, Feb 07 2007, and by M. F. Hasler, Jan 03 2014

STATUS

approved

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Last modified November 13 17:34 EST 2019. Contains 329106 sequences. (Running on oeis4.)