OFFSET
1,1
COMMENTS
All terms are prime, therefore 13143449029 is a base-7 circular prime, see A293660.
13143449029 is remarkable in that it has 12 digits in base 7 and may be the largest known nonrepunit circular prime in that base.
EXAMPLE
Base-7 expansion | Decimal value
---------------------------------
643464321244 | 13143449029
434643212446 | 8956420003
346432124464 | 7329791221
464321244643 | 9784676947
643212446434 | 13127589829
432124464346 | 8845405603
321244643464 | 6552690421
212446434643 | 4344971347
124464346432 | 2732225029
244643464321 | 5284288003
446434643212 | 9307441621
464346432124 | 9786942547
PROG
(PARI) rot(n) = if(#Str(n)==1, v=vector(1), v=vector(#n-1)); for(i=2, #n, v[i-1]=n[i]); u=vector(#n); for(i=1, #n, u[i]=n[i]); v=concat(v, u[1]); v
decimal(v, base) = my(w=[]); for(k=0, #v-1, w=concat(w, v[#v-k]*base^k)); sum(i=1, #w, w[i])
my(d=digits(13143449029, 7), e=d, v=[]); while(1, v=concat(v, [decimal(d, 7)]); d=rot(d); if(d==e, return(vecsort(v))))
CROSSREFS
KEYWORD
nonn,base,easy,fini,full
AUTHOR
Felix Fröhlich, Sep 26 2019
STATUS
approved