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A058371 The sequence S defined in A058540. 3
0, 0, 1, 3, 12, 48, 217, 1005, 4878, 24218, 123021, 634995, 3323963, 17596131, 94053675, 506865965, 2751093957, 15025119759, 82511460766, 455331632088, 2523688452540, 14042621802676, 78415665739800, 439298161502112, 2468288819015277 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..24.

MAPLE

spec := [ S, {N=Union(Z, S, P, Q), S=Set(Union(Z, P, Q), card>=2), P=Set(Union(Z, S, Q), card>=2), Q=Set(Union(Z, S, P), card>=2)} ]; [seq(combstruct[count](spec, size=n), n=0..40)]; # N=A058540, S=A058371

spec:=[S, {S=Set(Union(Z, S, S), card>=2)}]; [seq(combstruct[count](spec, size=n), n=0..25)]; - Vladeta Jovovic, Jun 25 2007

CROSSREFS

Cf. A058575.

Sequence in context: A142873 A151168 A151169 * A226443 A060113 A134589

Adjacent sequences:  A058368 A058369 A058370 * A058372 A058373 A058374

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Dec 26 2000

STATUS

approved

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Last modified July 28 06:29 EDT 2014. Contains 244987 sequences.