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A092621 Primes with exactly one prime digit. 18
2, 3, 5, 7, 13, 17, 29, 31, 43, 47, 59, 67, 71, 79, 83, 97, 103, 107, 113, 131, 139, 151, 163, 167, 179, 193, 197, 211, 241, 269, 281, 311, 349, 389, 421, 431, 439, 443, 463, 467, 479, 487, 509, 541, 569, 599, 607, 613, 617, 631, 643, 647, 659, 683, 701, 709 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Zak Seidov, Table of n, a(n) for n = 1..10000

FORMULA

a(n) >> n^1.28 because of the digit restriction

EXAMPLE

13 is prime and it has one prime digit, 3;

103 is prime and it has one prime digit, 3.

MAPLE

stev_sez:=proc(n) local i, tren, st, ans, anstren; ans:=[ ]: anstren:=[ ]: tren:=n: for i while (tren>0) do st:=round( 10*frac(tren/10) ): ans:=[ op(ans), st ]: tren:=trunc(tren/10): end do; for i from nops(ans) to 1 by -1 do anstren:=[ op(anstren), op(i, ans) ]; od; RETURN(anstren); end: ts_stpf:=proc(n) local i, stpf, ans; ans:=stev_sez(n): stpf:=0: for i from 1 to nops(ans) do if (isprime(op(i, ans))='true') then stpf:=stpf+1; # number of prime digits fi od; RETURN(stpf) end: ts_pr_prn:=proc(n) local i, stpf, ans, ans1, tren; ans:=[ ]: stpf:=0: tren:=1: for i from 1 to n do if ( isprime(i)='true' and ts_stpf(i) = 1) then ans:=[ op(ans), i ]: tren:=tren+1; fi od; RETURN(ans) end: ts_pr_prn(1000);

MATHEMATICA

podQ[n_]:=(1==Length@Select[IntegerDigits[n], PrimeQ]); Select[Prime[Range[250]], podQ](* Zak Seidov *)

PROG

(Sage) A092621 = list(p for p in primes(1000) if len([d for d in p.digits() if is_prime(d)]) == 1)

(PARI) isok(n) = isprime(n) && (d = digits(n)) && (sum(i=1, #d, isprime(d[i])) == 1); \\ Michel Marcus, Mar 10 2014

CROSSREFS

Cf. A034844, A092620.

Cf. A239037 (prime digit in A092621(n)). - Zak Seidov, Mar 10 2014

Sequence in context: A001000 A094947 A231474 * A188809 A152449 A048975

Adjacent sequences:  A092618 A092619 A092620 * A092622 A092623 A092624

KEYWORD

nonn,base

AUTHOR

Jani Melik, Apr 11 2004

STATUS

approved

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Last modified May 19 08:25 EDT 2019. Contains 323389 sequences. (Running on oeis4.)