A344884 - OEIS

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A344884

a(n) = 1 if A011772(n) divides A344875(n), otherwise 0; characteristic function of A344974.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 0

(list; graph; refs; listen; history; text; internal format)

OFFSET

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

Index entries for characteristic functions

FORMULA

a(n) >= A344885(n) >= A010055(n).

PROG

(PARI)

A011772(n) = { if(n==1, return(1)); my(f=factor(if(n%2, n, 2*n)), step=vecmax(vector(#f~, i, f[i, 1]^f[i, 2]))); forstep(m=step, 2*n, step, if(m*(m-1)/2%n==0, return(m-1)); if(m*(m+1)/2%n==0, return(m))); }; \\ From A011772

A344875(n) = { my(f=factor(n)~); prod(i=1, #f, (f[1, i]^(f[2, i]+(2==f[1, i]))-1)); };

A344884(n) = !(A344875(n)%A011772(n));

CROSSREFS

Characteristic function of A344974.

Cf. A010055, A011772, A344875, A344880, A344885.

Sequence in context: A014383 A014152 A014295 * A228710 A103447 A354923

Adjacent sequences: A344881 A344882 A344883 * A344885 A344886 A344887

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jun 05 2021

STATUS

approved