login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A217679 Bases of plain and extended interbase translation of 234099253 to a new prime number in base 10. 3
2, 3, 4, 5, 20, 22, 25, 29, 39, 43, 46, 58, 70, 85, 88, 89, 98, 99, 103, 105, 108, 116, 119, 122, 126, 142, 144, 154, 170 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These are the bases for A217673(4) (shown through the first case for which prime iterations reach a single digit), that sequence's example.  A217680 gives the number of times translation gives primes and fuller detail. 10 itself (and large bases that would not change the number) is (are) excluded.  Normal interbase translation is done by taking a smaller base's representation of a number and reads it as though the number were actually represented in a larger one, so here 'extended' signifies that 'digits' may be permitted to be more than 9.

LINKS

Table of n, a(n) for n=1..29.

EXAMPLE

234099253=47*170^3+110*170^2+54*170+73, and 47*10^3+110*10^2+54*10+73=58613, a prime; so 170 is included. This is the first base that reaches a prime smaller than it by iteration, with 58613 becoming 373 and 373 becoming 53.

CROSSREFS

Cf. A217673, A217680.

Sequence in context: A342617 A329579 A024635 * A248901 A280849 A037400

Adjacent sequences:  A217676 A217677 A217678 * A217680 A217681 A217682

KEYWORD

nonn,fini,less,base

AUTHOR

James G. Merickel, Oct 10 2012

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 28 09:54 EDT 2021. Contains 346326 sequences. (Running on oeis4.)