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Revision History for A049322

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A049322

Duplicate of A014557.
(history; published version)

#4 by N. J. A. Sloane at Fri May 11 03:00:00 EDT 2007

NAME

Same as Duplicate of A014557.

#3 by N. J. A. Sloane at Sat Jun 12 03:00:00 EDT 2004

NAME

Multiplicity of K_3 in K_n.

Same as A014557.

DATA

0, 0, 0, 0, 0, 0, 2, 4, 8, 12, 20, 28, 40, 52, 70, 88, 112, 136, 168, 200, 240, 280, 330, 380, 440, 500, 572, 644, 728, 812, 910, 1008, 1120, 1232, 1360, 1488, 1632, 1776, 1938, 2100, 2280, 2460, 2660, 2860, 3080, 3300, 3542, 3784, 4048, 4312

REFERENCES

V. Vijayalakshmi, Multiplicity of triangles in cocktail party graphs, Discrete Math., 206 (1999), 217-218.

MAPLE

A049322:=proc(n) local u; if n mod 2 = 0 then u:=n/2; RETURN(u*(u-1)*(u-2)/3); elif n mod 4 = 1 then u:=(n-1)/4; RETURN(u*(u-1)*(4*u+1)*2/3); else u:=(n-3)/4; RETURN(u*(u+1)*(4*u-1)*2/3); fi; end;

CROSSREFS

Twice A008804.

KEYWORD

nonn,nice,easy,new

dead

AUTHOR

njas

#2 by N. J. A. Sloane at Mon May 08 03:00:00 EDT 2000

MAPLE

aA049322:=proc(n) local u; if n mod 2 = 0 then u:=n/2; RETURN(u*(u-1)*(u-2)/3); elif n mod 4 = 1 then u:=(n-1)/4; RETURN(u*(u-1)*(4*u+1)*2/3); else u:=(n-3)/4; RETURN(u*(u+1)*(4*u-1)*2/3); fi; end;

KEYWORD

nonn,nice,easy,new

#1 by N. J. A. Sloane at Sat Dec 11 03:00:00 EST 1999

NAME

Multiplicity of K_3 in K_n.

DATA

OFFSET

0,7

REFERENCES

V. Vijayalakshmi, Multiplicity of triangles in cocktail party graphs, Discrete Math., 206 (1999), 217-218.

MAPLE

a:=proc(n) local u; if n mod 2 = 0 then u:=n/2; RETURN(u*(u-1)*(u-2)/3); elif n mod 4 = 1 then u:=(n-1)/4; RETURN(u*(u-1)*(4*u+1)*2/3); else u:=(n-3)/4; RETURN(u*(u+1)*(4*u-1)*2/3); fi; end;

CROSSREFS

Twice A008804.

KEYWORD

nonn,nice,easy

AUTHOR

njas

STATUS

approved