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A254861 Count of primes less than 10^n that do not contain the string n. 0
0, 4, 22, 102, 903, 6310, 46706, 266823, 2774348, 16531372 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..9.

EXAMPLE

When n = 1, there are four primes less than 10: 2, 3, 5, and 7. None of these have 1 as a digit so a(1) = 4.

MATHEMATICA

f[n_] := Block[{i}, Flatten@ Map[Length, Last@ Reap@ For[i = 0, i <= n, i++, Sow@ Select[Range[10^i], PrimeQ@ # && DigitCount[#][[i]] == 0 &]], {2}]]; f@ 7 (* Michael De Vlieger, Mar 26 2015 *)

PROG

(Sage) [len([p for p in prime_range(10^n) if not(str(n) in str(p))]) for n in [1..9]] # Tom Edgar, Feb 17 2015

CROSSREFS

Cf. A006880.

Sequence in context: A079272 A197667 A007901 * A088581 A017970 A220740

Adjacent sequences:  A254858 A254859 A254860 * A254862 A254863 A254864

KEYWORD

nonn,base,more

AUTHOR

Asa Kaplan, Feb 09 2015

EXTENSIONS

a(7)-a(9) from Tom Edgar, Feb 17 2015

STATUS

approved

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Last modified May 31 10:42 EDT 2020. Contains 334748 sequences. (Running on oeis4.)