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A323907
Lexicographically earliest positive sequence such that a(i) = a(j) => A004718(i) = A004718(j), for all i, j >= 0.
4
1, 2, 3, 4, 2, 1, 5, 6, 3, 4, 1, 2, 4, 3, 7, 8, 2, 1, 5, 6, 1, 2, 3, 4, 5, 6, 2, 1, 6, 5, 9, 10, 3, 4, 1, 2, 4, 3, 7, 8, 1, 2, 3, 4, 2, 1, 5, 6, 4, 3, 7, 8, 3, 4, 1, 2, 7, 8, 4, 3, 8, 7, 11, 12, 2, 1, 5, 6, 1, 2, 3, 4, 5, 6, 2, 1, 6, 5, 9, 10, 1, 2, 3, 4, 2, 1, 5, 6, 3, 4, 1, 2, 4, 3, 7, 8, 5, 6, 2, 1, 6, 5, 9, 10, 2, 1
OFFSET
0,2
COMMENTS
Restricted growth sequence transform of A004718, Per Nørgård's "infinity sequence".
The composer Per Nørgård's name is also written in the OEIS as Per Noergaard.
LINKS
PROG
(PARI)
up_to = 65535;
rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om, invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om, invec[i], i); outvec[i] = u; u++ )); outvec; };
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]);
v323907 = rgs_transform(vector(1+up_to, n, A004718(n-1)));
A323907(n) = v323907[1+n];
CROSSREFS
Restricted growth sequence transform of A004718, A323908 and A323909.
Cf. A083866 (positions of ones).
Sequence in context: A107474 A114734 A299755 * A375127 A214065 A378053
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 09 2019
STATUS
approved