A344874 a(n) = A047994(n) - A011772(n).

0, -2, 0, -4, 0, -1, 0, -8, 0, 0, 0, -2, 0, -1, 3, -16, 0, 0, 0, -3, 6, -1, 0, -1, 0, 0, 0, 11, 0, -7, 0, -32, 9, 0, 10, 16, 0, -1, 12, 13, 0, -8, 0, -2, 23, -1, 0, -2, 0, 0, 15, -3, 0, -1, 30, -6, 18, 0, 0, 9, 0, -1, 21, -64, 23, 9, 0, 32, 21, 4, 0, -7, 0, 0, 24, -2, 39, 12, 0, -4, 0, 0, 0, -12, 30, -1, 27, 38, 0, -3, 59

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..16384

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
A047994(n) = { my(f=factor(n)~); prod(i=1, #f, f[1, i]^f[2, i]-1); };
A344874(n) = (A047994(n)-A011772(n));

Crossrefs

Cf. A011772, A047994.

Cf. also A344763, A344765, A344876.

Sequence in context: A102392 A227311 A178515 * A051517 A289359 A356771

Adjacent sequences: A344871 A344872 A344873 * A344875 A344876 A344877

Keyword

sign

Author

Antti Karttunen, Jun 03 2021

Status

approved