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%I #12 Jul 04 2017 09:01:30
%S 15,13544240,138446293905,122914516488960,25999554922206250,
%T 2153128175383358880,92188903926678792030,2420834781123276840960,
%U 43619102772258066624945,582825001391348708850000,6107144216640392108077895,52317129545418639168933120
%N 1/24 the number of colorings of a 5 X 5 octagonal array with n colors.
%H Alois P. Heinz, <a href="/A068252/b068252.txt">Table of n, a(n) for n = 4..1000</a>
%H Alois P. Heinz, <a href="/A068252/a068252.txt">Formula for A068252</a>
%p a:= n-> (749775400182+ (-5612178463551+ (20061456442182+ (-45672704671212+ (74464103614803+ (-92636079268387+ (91447345270476+ (-73522860568402+ (49016457219873+ (-27440963053418+ (13013052032729+ (-5257328793792+
%p (1815373485182+ (-536334824998+ (135430280705+ (-29134045002+ (5309217327+ (-812594023+ (103170636+ (-10676360+ (877812+ (-55183+ (2492+(-72+n)*n) *n)*n) *n)*n) *n)*n) *n)*n) *n)*n) *n)*n) *n)*n) *n) *n) *n) *n) *n) *n) *n) *n) *n/24:
%p seq(a(n), n=4..20); # _Alois P. Heinz_, May 04 2012
%Y Cf. A068239-A068305, A000332, A002417, A027441, A212208, A212209.
%K nonn
%O 4,1
%A _R. H. Hardin_, Feb 24 2002
%E Extended beyond a(9) by _Alois P. Heinz_, May 04 2012
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