OFFSET
1,1
COMMENTS
This subsequence of A166512 consists of the numbers that can be split up in (at least) three different ways, n=concat(a,b)=concat(c,d)=concat(e,f), such that the sequences S(a,b), S(c,d) and S(e,f) all contain n.
LINKS
E. Angelini, k-comma numbers, Oct. 2009.
E. Angelini, k-comma numbers [Cached copy, with permission]
EXAMPLE
PROG
(PARI) {for(n=1e4, 1e5, /*is_A166513(n)=*/ my(c=3); for(d=1, #Str(n)-1, d+c>#Str(n) & break; my( a=n\10^d, b=n%10^d ); b<10^(d-1) & (d>1 | a%10==0) & next; while(n > b=10*(a%10)+b\10^(#Str(b)-1)+a=b, ); b==n & c--==0 & /*return(1)*/ !print1(n", ") & break))}
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Eric Angelini and M. F. Hasler, Oct 29 2009
STATUS
approved