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A090052 Group-abundant numbers: n such that the number of groups of order n (A000001) exceeds n. 0
1, 32, 48, 64, 96, 128, 144, 160, 192, 256, 288, 320, 384, 432, 448, 480, 512, 576, 640, 648, 672, 704, 720, 768, 800, 832, 864, 896, 960, 1024, 1088, 1152, 1216, 1248, 1280, 1296, 1344, 1408, 1440, 1458, 1536, 1600, 1664, 1728, 1792, 1920 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

It seems fairly certain that 1 is the only group-perfect number and that almost all numbers are group-deficient. However, all that is known at present is that all squarefree numbers are group-deficient.

CROSSREFS

Cf. A000001.

Sequence in context: A114416 A046304 A114447 * A163285 A036329 A014614

Adjacent sequences:  A090049 A090050 A090051 * A090053 A090054 A090055

KEYWORD

nonn

AUTHOR

John Conway (conway(AT)Math.Princeton.EDU), Jan 21 2004

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Last modified February 15 04:23 EST 2012. Contains 205694 sequences.