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 A036953 Primes containing only digits from the set {0, 1, 2}. 15

%I

%S 2,11,101,211,1021,1201,2011,2111,2221,10111,10211,12011,12101,12211,

%T 20011,20021,20101,20201,21001,21011,21101,21121,21211,21221,22111,

%U 101021,101111,101221,102001,102101,102121,110221,111121,111211,112111

%N Primes containing only digits from the set {0, 1, 2}.

%C 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

%C Also, primes in A007089. - _M. F. Hasler_, Jul 25 2015

%H Zak Seidov, <a href="/A036953/b036953.txt">Table of n, a(n) for n = 1..10000</a>

%H James Maynard and Brady Haran, <a href="https://www.youtube.com/watch?v=eeoBCS7IEqs">Primes without a 7</a>, Numberphile video (2019)

%t Select[FromDigits/@Tuples[{0,1,2},6],PrimeQ] (* _Harvey P. Dale_, Jul 11 2017 *)

%o (Python) from gmpy2 import digits

%o from sympy import isprime

%o [int(digits(n,3)) for n in range(1000) if isprime(int(digits(n,3)))] # _Chai Wah Wu_, Jul 31 2014

%o (PARI) lista(n) = {forprime(p=2, n, if (vecmax(digits(p)) <= 2, print1(p, ", ")))} \\ _Michel Marcus_, Aug 02 2014

%o (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

%Y Cf. A036952-A036964.

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

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Jan 04 1999

%E Edited by _M. F. Hasler_, Jul 25 2015

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Last modified September 29 12:15 EDT 2020. Contains 337431 sequences. (Running on oeis4.)