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A175280 Base-9 pandigital primes: primes having at least one of each digit 0,...,8 when written in base 9. 3
393474749, 393474821, 393475373, 393481069, 393486901, 393488437, 393492797, 393494477, 393499429, 393499517, 393500741, 393528029, 393528517, 393538157, 393541693, 393544709, 393545861, 393546149, 393551189, 393551357, 393552629 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Terms in this sequence have at least 10 digits in base 9, i.e., are larger than 9^9, since sum(d_i 9^i) = sum(d_i) (mod 8), and 0+1+2+3+4+5+6+7+8 is divisible by 4. So there must be at least one repeated digit, which may not be even, else the resulting number is even. The smallest terms are therefore of the form "10123...." in base 9, where "...." is a permutation of "45678", cf. examples.

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

The first terms of this sequence, i.e., smallest base-9 pandigital primes, are "1012346785", "1012346875", "1012347658", "1012356487", "1012365487", "1012367584", "1012374568", "1012376845", "1012384657", ... (written in base 9).

PROG

(PARI) pdp( b=9/*base*/, c=99/* # of terms to produce */) = { my(t, a=[], bp=vector(b, i, b^(b-i))~, offset=b*(b^b-1)/(b-1)); for( i=1, b-1, offset+=b^b; for( j=0, b!-1, isprime(t=offset-numtoperm(b, j)*bp) | next; #(a=concat(a, t))<c | return(vecsort(a))))} /* NOTE: Due to the implementation of numtoperm, the returned list may be incomplete towards its end. Thus computation of more than the required # of terms is recommended. [The initial digits of the base-9 expansion of the terms allow one to know up to where it is complete.] One may use a construct of the form: vecextract(pdp(9, 199), "1..20")) */

CROSSREFS

Cf. A138837, A050288, A175271 - A175279.

Sequence in context: A319358 A276274 A058125 * A271022 A015369 A321138

Adjacent sequences:  A175277 A175278 A175279 * A175281 A175282 A175283

KEYWORD

nonn,base

AUTHOR

M. F. Hasler, May 30 2010

EXTENSIONS

Edited by Charles R Greathouse IV, Aug 02 2010

STATUS

approved

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Last modified July 12 21:31 EDT 2020. Contains 335669 sequences. (Running on oeis4.)