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A007905 Conflicts during insertions into exchange trees on n nodes. 0
0, 0, 1, 4, 30, 216, 1440, 11040, 112560, 1229760, 14333760, 179988480, 2259290880, 30656102400, 446269824000, 6949355212800, 123855443712000, 2320686111744000, 45616912653312000, 939726185029632000, 20166054423330816000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..20.

Markus E. Nebel, Digital Search Trees with Keys of Variable Length, R.A.I.R.O. Theoretical Informatics and Applications 30 (6), 1996, 507 - 520 (see (3) on p. 6).

Index entries for sequences related to trees

FORMULA

See Pari program.

PROG

(PARI) b(n) = if (n == 0, 0, if (n == 1, 0, b(n\2) + b((n-1)\2) + (n-1)/n));

lista(nn) = {for(n=0, nn, print1(n!*b(n), ", "); ); } \\ Michel Marcus, Aug 13 2013

CROSSREFS

Sequence in context: A246151 A094567 A134093 * A084976 A000313 A082144

Adjacent sequences:  A007902 A007903 A007904 * A007906 A007907 A007908

KEYWORD

nonn

AUTHOR

Markus Nebel [ nebel(AT)sads.informatik.uni-frankfurt.de ]

EXTENSIONS

More terms from Michel Marcus, Aug 15 2013

STATUS

approved

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Last modified May 28 21:38 EDT 2017. Contains 287241 sequences.