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A331173
a(n) = min(n, A263273(n)), where A263273 is bijective base-3 reverse.
3
0, 1, 2, 3, 4, 5, 6, 5, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 11, 20, 15, 14, 23, 24, 17, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 31, 38, 39, 40, 41, 42, 43, 44, 45, 34, 47, 48, 43, 50, 51, 52, 53, 54, 29, 56, 33, 38, 59, 60, 47, 62, 45, 32, 59, 42, 41, 68, 69, 50, 71, 72, 35, 62, 51, 44, 71, 78, 53, 80, 81
OFFSET
0,3
COMMENTS
For all i, j:
a(i) = a(j) => A290094(i) = A290094(j).
For all i, j > 0:
a(i) = a(j) => A007949(i) = A007949(j).
LINKS
PROG
(PARI)
A030102(n) = { my(r=[n%3]); while(0<n\=3, r=concat(n%3, r)); subst(Polrev(r), x, 3); } \\ After code in A030102.
A263273 = n -> if(!n, n, A030102(n/(3^valuation(n, 3))) * (3^valuation(n, 3)));
A331173(n) = min(n, A263273(n));
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Jan 12 2020
STATUS
approved