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.

A175272 Base-12 pandigital primes.

Original entry on oeis.org

8989787252711, 8989787311891, 8989787313343, 8989787458763, 8989787707627, 8989787709211, 8989787710927, 8989787764211, 8989787806099, 8989787810719, 8989787959879, 8989787974883, 8989787992747, 8989787999743, 8989788058351
Offset: 1

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Author

M. F. Hasler, Mar 19 2010

Keywords

Comments

These numbers need to have at least 13 digits in base 12 since any permutation of the digits 0,...,9,A,B will result in a number divisible by 11. For the same reason, it must be digit different from 0 which is repeated. Thus the smallest terms in this sequence are written "10123456....." in base 12, where ..... is a permutation of {7,8,9,A,B}.
Note: Due to the implementation of numtoperm(), the PARI script will not necessarily print the terms in the correct order. In some cases, more than the desired number of terms have to be calculated, and vecsort() to be used to get the correct sequence. - M. F. Hasler, May 27 2010

Examples

			8989787252711, 8989787311891, 8989787313343, 8989787458763, ... are written "101234568A79B", "10123456B8A97", "10123456B98A7", "1012345769A8B", ... in base 12 (where A=digit 10, B=digit 11).
		

Crossrefs

Programs

  • PARI
    pdp( b=12/* base */, c=20/* #terms to print */)={ my(t,bp=vector(b,i,b^(b-i))~, offset=b*(b^b-1)/(b-1) /* to fix order of permutations CBA..321 => 012...9AB */); for( i=1,b-1, /* add initial digit */ offset += b^b; for( j=0,b!-1, isprime(t=offset-numtoperm(b,j)*bp) & !print1(t", ") & !c-- & return))}

Extensions

Order of the terms corrected by M. F. Hasler, May 27 2010