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A098224 Number of primes <=10^n in which decimal digits are all distinct. 5
4, 24, 121, 631, 3160, 13399, 47349, 137859, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086, 283086 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Partial sums of A073532. - Lekraj Beedassy, Aug 02 2008

No number with more than 10 digits can have all of its decimal digits distinct, and no number that uses all ten distinct decimal digits can be prime (because the sum of all ten decimal digits is 45 so any such number is divisible by 3).  Therefore, every term in the sequence from and after a(9) is the same, i.e., 283086. - Harvey P. Dale, Dec 12 2010

LINKS

Table of n, a(n) for n=1..35.

FORMULA

a(n) = 283086 for n >= 9.

MATHEMATICA

okQ[n_]:=Max[DigitCount[n]]==1

Table[Length[Select[Prime[Range[PrimePi[10^i]]], okQ]], {i, 9}] (* Harvey P. Dale, Dec 12 2010 *)

PROG

(Python)

from sympy import sieve

def distinct_digs(n): s = str(n); return len(s) == len(set(s))

def aupton(terms):

  ps, alst = 0, []

  for n in range(1, terms+1):

    if n >= 10: alst.append(ps); continue

    ps += sum(distinct_digs(p) for p in sieve.primerange(10**(n-1), 10**n))

    alst.append(ps)

  return alst

print(aupton(35)) # Michael S. Branicky, Apr 24 2021

CROSSREFS

Cf. A006880, A006879, A073532, A098226-A098227.

Sequence in context: A273444 A049315 A295506 * A339123 A024049 A103455

Adjacent sequences:  A098221 A098222 A098223 * A098225 A098226 A098227

KEYWORD

base,nonn

AUTHOR

Labos Elemer, Oct 26 2004

STATUS

approved

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Last modified July 29 12:40 EDT 2021. Contains 346346 sequences. (Running on oeis4.)