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
James Maynard and Brady Haran, Primes without a 7, Numberphile video (2019)
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
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Jan 04 1999
EXTENSIONS
Edited by M. F. Hasler, Jul 25 2015
STATUS
approved