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A125203 Number of ways to write n as 4*x*y - x - y with 1<=x<=y. 6
0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 2, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 2, 0, 0, 1, 0, 0, 2, 0, 0, 1, 0, 1, 1, 1, 0, 2, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 2, 0, 0, 2, 0, 0, 2, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 2, 0, 0, 2, 1, 0, 1, 0, 0, 1, 2, 0, 1, 0, 0, 2, 0, 1, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,26

COMMENTS

a(A094178(n))=0; a(A124934(n))>0; a(A125217(n))=1; a(A125218(n))>1.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

PROG

(Haskell)

a125203 n = length [() | x <- [1 .. (n + 1) `div` 3],

                         let (y, m) = divMod (x + n) (4 * x - 1),

                         x <= y, m == 0]

-- Reinhard Zumkeller, Jan 02 2013

CROSSREFS

Cf. A193773.

Sequence in context: A309367 A122179 A335877 * A023565 A321925 A025922

Adjacent sequences:  A125200 A125201 A125202 * A125204 A125205 A125206

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Nov 24 2006

STATUS

approved

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Last modified May 14 16:10 EDT 2021. Contains 343884 sequences. (Running on oeis4.)