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A361016
a(n) = 1 if A004718(n) = 0, otherwise 0, where A004718 is the Danish composer Per Nørgård's "infinity sequence".
2
1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0
OFFSET
0
COMMENTS
The composer Per Nørgård's name is also written in the OEIS as Per Noergaard.
FORMULA
a(n) = [A004718(n) = 0] = [A343029(n) = A343030(n)], where [ ] is the Iverson bracket.
PROG
(PARI)
up_to = 65537;
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 Charles R Greathouse IV's Nov 18 2011 code in A004718.
v004718 = A004718list(up_to);
A004718(n) = if(!n, n, v004718[n]);
A361016(n) = !A004718(n);
(Python)
from itertools import groupby
def A361016(n):
c = 0
for k, g in groupby(bin(n)[2:]):
c = c+len(list(g)) if k == '1' else (-c if len(list(g))&1 else c)
return int(not c) # Chai Wah Wu, Mar 02 2023
CROSSREFS
Characteristic function of A083866.
Sequence in context: A133943 A014084 A014159 * A014184 A014359 A079998
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 02 2023
STATUS
approved