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A273969 Numbers n such that there exists a pair x,y, where x<y, x! = n and y! = n, that makes {x,y,n,n} an amicable multiset. 3
702240, 817740, 1156680, 1159200, 1811040, 2450448, 2570400, 2784600, 3534300, 3912480, 4228560, 4546080, 4702320, 5682600, 6902280, 7280280, 7469280, 7706160, 8225280, 8316000, 8465184, 8522640, 8639400, 9025380, 9256800, 9282000, 9492120, 9828000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

We call the multiset {x,y,n,n} amicable iff sigma(x) = sigma(y) = sigma(n) = x+y+n+n. For the x values, see A273970. For the y values, see A273971.

If the condition x<y were dropped, the terms from A259306 would also belong here.

LINKS

John Cerkan, Table of n, a(n) for n = 1..8082

John Cerkan, Python code

EXAMPLE

sigma(695520) = sigma(803040) = sigma(702240) = 695520 + 803040 + 702240 + 702240.

CROSSREFS

Cf. A259302, A259303, A259304, A259305, A259306, A273970, A273971.

Sequence in context: A204496 A332850 A183835 * A203834 A234701 A140943

Adjacent sequences:  A273966 A273967 A273968 * A273970 A273971 A273972

KEYWORD

nonn

AUTHOR

John Cerkan, Jul 17 2016

STATUS

approved

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Last modified September 22 21:07 EDT 2020. Contains 337291 sequences. (Running on oeis4.)