A323909 Balanced ternary representation of A004718, Per Nørgård's "infinity sequence".

0, 1, 2, 5, 1, 0, 7, 3, 2, 5, 0, 1, 5, 2, 6, 4, 1, 0, 7, 3, 0, 1, 2, 5, 7, 3, 1, 0, 3, 7, 8, 17, 2, 5, 0, 1, 5, 2, 6, 4, 0, 1, 2, 5, 1, 0, 7, 3, 5, 2, 6, 4, 2, 5, 0, 1, 6, 4, 5, 2, 4, 6, 22, 15, 1, 0, 7, 3, 0, 1, 2, 5, 7, 3, 1, 0, 3, 7, 8, 17, 0, 1, 2, 5, 1, 0, 7, 3, 2, 5, 0, 1, 5, 2, 6, 4, 7, 3, 1, 0, 3, 7, 8, 17, 1, 0

Offset

0,3

Comments

The composer Per Nørgård's name is also written in the OEIS as Per Noergaard.

Links

Antti Karttunen, Table of n, a(n) for n = 0..65536

Formula

If A004718(n) >= 0, then a(n) = A117967(A004718(n)), otherwise a(n) = A117968(-A004718(n)).

For all n >= 1, A117966(a(n)) = A004718(n).

Prog

(PARI)
up_to = 65536;
A004718list(up_to) = { my(v=vector(up_to)); v[1]=1; v[2]=-1; for(n=3, up_to, v[n] = if(n%2, 1+v[n>>1], -v[n/2])); (v); }; \\ After code in A004718.
v004718 = A004718list(up_to);
A004718(n) = if(!n, n, v004718[n]);
A117967(n) = if(n<=1, n, if(!(n%3), 3*A117967(n/3), if(1==(n%3), 1+3*A117967((n-1)/3), 2+3*A117967((n+1)/3))));
A117968(n) = if(1==n, 2, if(!(n%3), 3*A117968(n/3), if(1==(n%3), 2+3*A117968((n-1)/3), 1+3*A117968((n+1)/3))));
A323909(n) = { my(x = A004718(n)); if(x >= 0, A117967(x), A117968(-x)); };

Crossrefs

Cf. A004718, A083866 (positions of zeros), A117966, A117967, A117968, A323907 (rgs-transform), A323908.

Sequence in context: A381384 A011217 A078506 * A124779 A284750 A092134

Adjacent sequences: A323906 A323907 A323908 * A323910 A323911 A323912

Keyword

nonn

Author

Antti Karttunen, Feb 10 2019

Status

approved