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A210288
Number of 2 X 2 matrices with all elements in {0,1,...,n} and permanent = trace.
3
1, 6, 19, 29, 41, 51, 65, 75, 89, 101, 115, 125, 143, 153, 167, 181, 197, 207, 225, 235, 253, 267, 281, 291, 313, 325, 339, 353, 371, 381, 403, 413, 431, 445, 459, 473, 497, 507, 521, 535, 557, 567, 589, 599, 617, 635
OFFSET
0,2
COMMENTS
See A210000 for a guide to related sequences.
MATHEMATICA
a = 0; b = n; z1 = 45;
t[n_] := t[n] = Flatten[Table[w + z - w*z - x*y, {w, a, b}, {x, a, b}, {y, a, b}, {z, a, b}]]
c[n_, k_] := c[n, k] = Count[t[n], k]
Table[c[n, 0], {n, 0, z1}] (* A210288 *)
CROSSREFS
Cf. A210000.
Sequence in context: A041911 A372302 A341327 * A038125 A319968 A277402
KEYWORD
nonn
AUTHOR
Clark Kimberling, Mar 19 2012
STATUS
approved