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A131674
Size of the largest BDD of symmetric Boolean functions of n variables when the sink nodes are not counted.
1
0, 1, 3, 5, 8, 12, 17, 23, 29, 36, 44, 53, 63, 74, 86, 99, 113, 127, 142, 158, 175, 193, 212, 232, 253, 275, 298, 322, 347, 373, 400, 428, 457, 487, 517, 548, 580, 613, 647, 682, 718, 755, 793, 832, 872, 913, 955, 998, 1042, 1087, 1133, 1180, 1228, 1277, 1327, 1378, 1430, 1483
OFFSET
0,3
REFERENCES
Mark Heap, On the exact ordered binary decision diagram size of totally symmetric functions, Journal of Electronic Testing 4 (1993), 191-195.
Ingo Wegener, Optimal decision trees and one-time-only branching programs for symmetric Boolean functions, Information and Control 62 (1984), 129-143.
FORMULA
a(n) = sum_{k=1..n} min(k,2^{n+2-k}-2).
MATHEMATICA
f[n_] := Sum[ Min[k, 2^{n + 2 - k} - 2], {k, n}]; Table[ f@n, {n, 0, 57}] (* Robert G. Wilson v, Sep 16 2007 *)
CROSSREFS
See A131673 for another version.
Sequence in context: A014811 A282513 A241567 * A095173 A002579 A023544
KEYWORD
nonn,easy
AUTHOR
Don Knuth, Sep 06 2007
STATUS
approved