OFFSET
1,1
COMMENTS
There are exactly 68 right truncatable primes in base 9.
LINKS
Martin Renner, Table of n, a(n) for n = 1..68
I. O. Angell, and H. J. Godwin, On Truncatable Primes, Math. Comput. 31, 265-267, 1977.
Eric Weisstein's World of Mathematics, Truncatable Prime.
MAPLE
Extend:= proc(n) op(select(isprime, [seq(9*n+k, k=1..8)])) end proc:
S:= {}: Agenda:= {2, 3, 5, 7}:
while Agenda <> {} do
S:= S union Agenda;
Agenda:= map(Extend, Agenda);
od:
sort(convert(S, list)); # Robert Israel, Mar 25 2018
CROSSREFS
KEYWORD
nonn,base,fini,full
AUTHOR
Martin Renner, Jun 01 2007
STATUS
approved