OFFSET
1,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
Chris Caldwell, The Prime Glossary, Unholey prime
FORMULA
a(n) >> n^k where k = log(10)/log(5) = 1.43067.... - Charles R Greathouse IV, Dec 28 2017
MATHEMATICA
Join[{1}, Select[Range[2000], PrimeQ[#] && Intersection[{0, 4, 6, 8, 9}, IntegerDigits[#]] == {} &]] (* T. D. Noe, May 09 2011 *)
PROG
(Magma) [1] cat [n: n in PrimesUpTo(1223) | Set(Intseq(n)) subset [1, 2, 3, 5, 7]]; // Arkadiusz Wesolowski, Apr 16 2014
(PARI) is(k) = if(!isprime(k) && k != 1, return(0)); setminus(vecsort(digits(k), , 8), [1, 2, 3, 5, 7]) == [] \\ Iain Fox, Dec 28 2017
(PARI) is(n) = if(isprime(n), #setminus(Set(digits(k)), [1, 2, 3, 5, 7])==0, n==1) \\ Charles R Greathouse IV, Dec 28 2017
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Jaroslav Krizek, May 06 2011
STATUS
approved