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A068270 1/20 the number of colorings of an n X n square array with 20 colors. 1
1, 6517, 13841287219, 9580458187250990407, 2161111220298293067819628379911, 158872597397775739573835110149847235229271675, 3806290340846629510463844992746098005507806101928649895595171, 29719114772241665792629546781476756531800106771541628945462624575440369135473679 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..8.

CROSSREFS

Cf. A068239-A068305, A000332, A002417, A027441, A182368, A182406.

Sequence in context: A156416 A156418 A258521 * A216666 A260979 A034627

Adjacent sequences:  A068267 A068268 A068269 * A068271 A068272 A068273

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 24 2002

EXTENSIONS

a(5)-a(8) from Alois P. Heinz, Apr 27 2012

STATUS

approved

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Last modified December 10 18:10 EST 2019. Contains 329901 sequences. (Running on oeis4.)