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A353340
Smallest positive number k such that there are exactly n integers b with k > b > 1 where the base-b representation of k is periodic.
0
1, 3, 5, 15, 10, 36, 80, 60, 120, 168, 260, 252, 360, 630, 504, 720, 840, 1512, 1260, 1800, 1680, 2340, 3276, 3120, 3360, 2520, 9072, 7200, 6300, 12096, 7920, 5040, 9240, 7560, 20520, 25920, 15840, 10080
OFFSET
0,2
PROG
(PARI) is(n, b) = for (w=1, oo, my (d=digits(n, b^w)); if (#d<=1, return (0), #Set(d)==1, return (1))) \\ after Rémy Sigrist in A321513
a353339(n) = my(i=0); for(b=2, n-1, if(is(n, b), i++)); i
a(n) = for(k=1, oo, if(a353339(k)==n, return(k)))
CROSSREFS
Cf. A353339.
Sequence in context: A332382 A277323 A340194 * A160046 A349553 A272024
KEYWORD
nonn,base,more
AUTHOR
Felix Fröhlich, Apr 14 2022
STATUS
approved