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A261786
Successively add the smallest ternary number that is not a substring.
5
1, 3, 5, 8, 9, 11, 15, 18, 19, 22, 25, 28, 30, 32, 36, 38, 43, 46, 49, 52, 55, 58, 61, 64, 68, 71, 74, 75, 79, 82, 84, 86, 90, 92, 96, 100, 104, 108, 110, 115, 120, 122, 125, 128, 131, 134, 137, 140, 143, 146, 150, 153, 156, 160, 163, 166, 169, 172, 176, 179
OFFSET
1,2
LINKS
PROG
(Haskell)
a261786 n = a261786_list !! (n-1)
a261786_list = iterate (\x -> x + a261787 x) 1
(PARI) ts(n) = Str(fromdigits(digits(n, 3))); \\ A007089
f(n) = my(s=ts(n), k=1); while (#strsplit(s, ts(k)) != 1, k++); k; \\ A261787
lista(nn) = my(v = vector(nn)); v[1] = 1; for (n=2, nn, v[n] = v[n-1] + f(v[n-1]); ); v; \\ Michel Marcus, Feb 06 2022
CROSSREFS
Cf. A007089, A261787, A261789 (first differences), A261788, A260273, A261793.
Sequence in context: A026223 A034784 A190280 * A124401 A292526 A151747
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Sep 01 2015
STATUS
approved