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A036953 Primes containing only digits from the set {0, 1, 2}. 15
2, 11, 101, 211, 1021, 1201, 2011, 2111, 2221, 10111, 10211, 12011, 12101, 12211, 20011, 20021, 20101, 20201, 21001, 21011, 21101, 21121, 21211, 21221, 22111, 101021, 101111, 101221, 102001, 102101, 102121, 110221, 111121, 111211, 112111 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of n-digit terms d(n) = (1, 1, 2, 5, 16, 34, 76, 194, 543, 1469, 4094, 11017, ...); e.g., there are five 4-digit terms: 1021, 1201, 2011, 2111, 2221, hence d(4) = 5. - Zak Seidov, Jun 30 2013

Also, primes in A007089. - M. F. Hasler, Jul 25 2015

LINKS

Zak Seidov, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[FromDigits/@Tuples[{0, 1, 2}, 6], PrimeQ] (* Harvey P. Dale, Jul 11 2017 *)

PROG

(Python) from gmpy2 import digits

from sympy import isprime

[int(digits(n, 3)) for n in range(1000) if isprime(int(digits(n, 3)))] # Chai Wah Wu, Jul 31 2014

(PARI) lista(n) = {forprime(p=2, n, if (vecmax(digits(p)) <= 2, print1(p, ", ")))} \\ Michel Marcus, Aug 02 2014

(PARI) A036953={(n, show=0)->for(d=1, 1e9, my(u=vector(d, i, 10^(d-i))~); forvec(v=vector(d, i, if(i>1, if(i<d, [0, 2], [1, 1]), [1, 2])), ispseudoprime(v*u)||next; show&&print1(v*u, ", "); n--||return(v*u)))} \\ M. F. Hasler, Jul 25 2015

CROSSREFS

Cf. A036952-A036964.

Cf. A020450 - A020472, A260044, A260267 - A260271, A199325 - A199329, A061247, A199340 - A199349, A217039, A079651.

Sequence in context: A048662 A229876 A090726 * A254320 A115062 A062397

Adjacent sequences:  A036950 A036951 A036952 * A036954 A036955 A036956

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jan 04 1999

EXTENSIONS

Edited by M. F. Hasler, Jul 25 2015

STATUS

approved

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Last modified September 23 15:54 EDT 2017. Contains 292361 sequences.