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A190222 Noncomposite numbers all of whose decimal digits are noncomposite numbers (1,2,3,5,7). 3
1, 2, 3, 5, 7, 11, 13, 17, 23, 31, 37, 53, 71, 73, 113, 127, 131, 137, 151, 157, 173, 211, 223, 227, 233, 251, 257, 271, 277, 311, 313, 317, 331, 337, 353, 373, 521, 523, 557, 571, 577, 727, 733, 751, 757, 773, 1117, 1123, 1151, 1153, 1171, 1213, 1217, 1223 (list; graph; refs; listen; history; text; internal format)
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

Subsequence of A001742.

Sequence in context: A038617 A036962 A160337 * A012884 A068669 A316412

Adjacent sequences:  A190219 A190220 A190221 * A190223 A190224 A190225

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, May 06 2011

STATUS

approved

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Last modified March 23 05:36 EDT 2019. Contains 321422 sequences. (Running on oeis4.)