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A320006
a(n) = 1 if n encodes a nonnegative combinatorial game (in a style of A106486), otherwise 0; Characteristic function of A126001.
4
1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
0
PROG
(PARI)
A320006(n) = if(!n, 1, my(m=(n>>1), r=0); while(m>0, if((m%2)&&!A320007(r), return(0)); m >>= 2; r++); (1));
A320007(n) = if(!n, 0, my(m=n, s=0); while(m>0, if((m%2)&&A320006(s), return(1)); m >>= 2; s++); (0));
CROSSREFS
Characteristic function of A126001. The topmost row of A125999.
Cf. A320007.
Sequence in context: A285345 A125999 A073784 * A219977 A128130 A133872
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 18 2018
STATUS
approved