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%I #12 Aug 09 2022 14:07:20
%S 1,17,131,709,3350,14337,57507,218746,803384,2870707,10044838,
%T 34548917,117224825,393290329,1307200931,4310348599,14116544717,
%U 45959805027,148860350902,479938536114,1541025955958,4929773150983
%N Number of oriented multidimensional n-ominoes with cell centers determining n-3 space.
%C Multidimensional polyominoes are connected sets of cells of regular tilings with Schläfli symbols {oo}, {4,4}, {4,3,4}, {4,3,3,4}, etc. Each tile is a regular orthotope (hypercube). This sequence is obtained using the first formula below. For oriented polyominoes, chiral pairs are counted as two.
%H W. F. Lunnon, <a href="http://dx.doi.org/10.1093/comjnl/18.4.366">Counting multidimensional polyominoes</a>. Computer Journal 18 (1975), no. 4, pp. 366-367.
%F a(n) = A355053(n) + A355054(n) = 2*A355053(n) - A355055(n) = 2*A355054(n) + A355055(n).
%F a(n) = A195738(n,n-3), the third diagonal of Lunnon's DR array.
%e a(4)=1 because there is just one tetromino (with four cells aligned) in 1-space. a(5)=17 because there are 5 achiral and 6 chiral pairs of pentominoes in 2-space, excluding the 1-D straight pentomino.
%Y Cf. A355053 (unoriented), A355054 (chiral), A355055 (achiral) A355056 (asymmetric), A191092 (fixed), A355047 (orthoplex), A195738 (Lunnon's DR).
%K nonn,easy
%O 4,2
%A _Robert A. Russell_, Jun 16 2022