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A092626 Primes with one nonprime digit. 4
13, 17, 29, 31, 43, 47, 59, 67, 71, 79, 83, 97, 127, 137, 157, 173, 229, 239, 251, 263, 271, 283, 293, 307, 313, 317, 331, 347, 359, 367, 379, 383, 397, 433, 457, 503, 521, 547, 563, 571, 587, 593, 653, 673, 677, 739, 743, 751, 787, 797, 823, 827, 853, 857 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Heuristically, there are 15/(8 log 10) * n^(log_10 4) members up to n, or about 0.814 * n^0.602.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

13 is prime and it has one nonprime digit, 1;

3259 is prime and it has one nonprime digit, 9.

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_stnepf:=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))='false') then stpf:=stpf+1; # number of nonprime digits fi od; RETURN(stpf) end:

ts_pr_neprn:=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_stnepf(i) = 1) then ans:=[ op(ans), i ]: tren:=tren+1; fi od; RETURN(ans) end: ts_pr_neprn(4000);

MATHEMATICA

Select[Prime[Range[200]], Count[IntegerDigits[#], _?(!PrimeQ[#]&)]==1&] (* Harvey P. Dale, Feb 18 2018 *)

CROSSREFS

Cf. A019546.

Sequence in context: A152427 A179909 A220488 * A156343 A154762 A079348

Adjacent sequences:  A092623 A092624 A092625 * A092627 A092628 A092629

KEYWORD

nonn,base,easy

AUTHOR

Jani Melik, Apr 11 2004

EXTENSIONS

Edited by R. J. Mathar, Nov 02 2009

Comment from Charles R Greathouse IV, Mar 19 2010

STATUS

approved

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Last modified April 24 00:02 EDT 2019. Contains 322404 sequences. (Running on oeis4.)