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A117311 Beginning with sequence A096903, choose only those rows such that when a(n) is in factored form all exponents of a(n) are consecutive starting at 1. 0
2, 6, 12, 18, 30, 60, 90, 150, 180, 300, 450, 210, 360, 540, 600, 1350, 1500, 2250, 420, 630, 1050, 1470, 1260, 2100, 2940, 3150, 4410, 7350, 2310, 2520, 3780, 4200, 5880, 9450, 10500, 13230, 15750, 20580, 30870, 36750, 51450, 4620, 6930, 11550, 16170 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Included rows can be mapped to permutation groups; e.g. - (12,18) to C2; (60,90,150) and (180,300,450) to C3; (360,540,600,1350,1500,2250) to S3; and (420,630,1050,1470) to C4.

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

10 is not a member of a(n) since it is not a term in A096903.

24 is not a member of a(n) since 24 = 2^3 * 3^1 and exponents 1 & 3 are not consecutive.

12, 60 and 180 are included since the exponents are (2,1), (2,1,1) & (2,2,1) respectively.

CROSSREFS

Cf. A055932 A084918 A096903.

Sequence in context: A113274 A181660 A036913 * A125024 A178480 A053660

Adjacent sequences:  A117308 A117309 A117310 * A117312 A117313 A117314

KEYWORD

nonn,tabf

AUTHOR

Alford Arnold, Mar 07 2006

EXTENSIONS

More terms from Franklin T. Adams-Watters, Nov 20 2006

STATUS

approved

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Last modified December 6 14:49 EST 2016. Contains 278781 sequences.