cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A175271 Base-8 pandigital primes.

Original entry on oeis.org

17119607, 17120573, 17121077, 17127839, 17128931, 17132347, 17135413, 17136029, 17136869, 17148349, 17159479, 17164757, 17181683, 17184119, 17185463, 17185981, 17194171, 17196383, 17196733, 17200373, 17202347
Offset: 1

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Author

M. F. Hasler, May 27 2010

Keywords

Comments

Base-8 pandigital primes must have at least 9 octal digits, since sum(d_i 8^i) = sum(d_i) (mod 7), and 0+1+...+6+7 is divisible by 7. So the smallest ones should be of the form "10123...." in base 8, where "...." is a permutation of "4567". By chance, the identical permutation already yields a prime: a(1)="101234567" in base-8.

Crossrefs

Programs

  • PARI
    pdp( b=8/*base*/, c=199/* # 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))
    				

Extensions

Edited by Charles R Greathouse IV, Aug 02 2010