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A260267 Primes that contain only digits in {1, 2, 4}. 7
2, 11, 41, 211, 241, 421, 2111, 2141, 2221, 2411, 2441, 4111, 4211, 4241, 4421, 4441, 11411, 12211, 12241, 12421, 14221, 14411, 21121, 21211, 21221, 22111, 22441, 24121, 24421, 41141, 41221, 41411, 42221, 44111, 44221, 111121, 111211, 112111, 112121, 112241 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A020450 and A020452 are subsequences.

All terms but the first one end with a digit "1". - M. F. Hasler, Jul 26 2015

LINKS

Table of n, a(n) for n=1..40.

Index to entries about primes with digits in a given set.

MATHEMATICA

Select[Prime[Range[3 10^4]], Complement[IntegerDigits[#], {1, 4, 2}]=={} &]

PROG

(MAGMA) [p: p in PrimesUpTo(4*10^5) | Set(Intseq(p)) subset [1, 4, 2]];

(PARI) A260267(n=50, show=0)={for(d=1, 1e9, my(t, u=vector(d, i, 10^(d-i))~); forvec(v=vector(d, i, [0, if(i<d, 2, d==1)]), ispseudoprime(t=vector(d, i, 1<<v[i])*u)||next; show&&print1(t", "); n--||return(t)))} \\ M. F. Hasler, Jul 25 2015

CROSSREFS

Cf. similar sequences listed in A260266.

Cf. A020450, A020452.

Sequence in context: A121244 A203574 A070778 * A128241 A258937 A225907

Adjacent sequences:  A260264 A260265 A260266 * A260268 A260269 A260270

KEYWORD

nonn,easy,base

AUTHOR

Vincenzo Librandi, Jul 23 2015

STATUS

approved

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