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A344595 Numbers k such that A011772(k) > A344878(k) and A011772(k) is a divisor of A344875(k). 4
900, 1260, 1302, 1560, 2100, 3906, 4440, 6300, 6552, 6669, 9680, 11544, 12987, 15368, 18981, 19240, 19880, 24120, 26208, 35784, 36080, 42680, 46104, 57720, 59040, 59640, 62238, 62244, 71136, 74592, 76840, 79376, 81872, 84700, 101680, 103730, 108500, 124488, 128040, 145188, 160160, 168020, 171740, 178920, 185724, 201608 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers k for which A344973(k) = 0 and A344976(k) < 0.

It seems that in these cases, by necessity A011772(k) < A344875(k), i.e., A011772(k) is a proper divisor of A344875(k).

Has many terms common with A344694.

LINKS

Table of n, a(n) for n=1..46.

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)); };

A344878(n) = if(1==n, n, my(f=factor(n)~); lcm(vector(#f, i, (f[1, i]^(f[2, i]+(2==f[1, i]))-1))));

isA344595(n) = { my(u=A011772(n)); (u>A344878(n)&&0==(A344875(n)%u)); };

CROSSREFS

Cf. A011772, A344694, A344875, A344878, A344973, A344976.

Intersection of A024619, A344974 and A344977.

Intersection of A344975 and A344977.

Sequence in context: A158408 A158409 A061044 * A344694 A127658 A318720

Adjacent sequences:  A344592 A344593 A344594 * A344596 A344597 A344598

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jun 05 2021

STATUS

approved

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Last modified August 5 04:03 EDT 2021. Contains 346457 sequences. (Running on oeis4.)