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A036628
Number of 4-ary rooted trees with n nodes and height exactly 4.
1
0, 0, 0, 0, 1, 3, 8, 18, 35, 65, 114, 194, 316, 510, 793, 1223, 1839, 2737, 3984, 5746, 8123, 11363, 15615, 21212, 28336, 37412, 48597, 62368, 78810, 98359, 120910, 146797, 175601, 207443, 241515, 277666, 314674, 352152, 388503
OFFSET
0,6
LINKS
E. M. Rains and N. J. A. Sloane, On Cayley's Enumeration of Alkanes (or 4-Valent Trees), J. Integer Sequences, Vol. 2 (1999), Article 99.1.1.
CROSSREFS
Sequence in context: A081489 A055278 A293349 * A004035 A169763 A227161
KEYWORD
nonn,fini,full
AUTHOR
STATUS
approved