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A083938
A014486-indices of binary trees whose left and right subtree are identical.
3
0, 1, 6, 42, 52, 385, 414, 477, 506, 555, 4089, 4180, 4388, 4479, 4645, 5095, 5186, 5394, 5485, 5651, 5969, 6060, 6226, 6502, 47363, 47661, 48366, 48664, 49237, 50800, 51098, 51803, 52101, 52674, 53808, 54106, 54679, 55681, 59311, 59609, 60314
OFFSET
0,3
COMMENTS
Fixed points of permutation A069770. Diagonal of A072764 (and A072766).
FORMULA
a(0)=0, a(n)=A072764bi(n-1, n-1).
CROSSREFS
a(n) = A080300(A083939(n)). Cf. A083940.
Sequence in context: A153243 A186885 A097253 * A292316 A329000 A329339
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 13 2003
STATUS
approved