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A098827 Squarefree oblong (pronic) having an odd number of factors. 0
2, 30, 42, 110, 182, 506, 1406, 2162, 3422, 3782, 4290, 4830, 5402, 6006, 6806, 11130, 11342, 12210, 13110, 16770, 23870, 24806, 27390, 27722, 31862, 33306, 34410, 34782, 37442, 37830, 44310, 49062, 51302, 56406, 60762, 64770, 66822, 68906 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..38.

EXAMPLE

a(1)=2 is oblong and squarefree

MAPLE

ts_nsq_pronic:=proc(n) local i, ans; ans:=[ ]: for i from 1 to n do if (numtheory[mobius]( i*(i+1) ) = -1 ) then ans:=[ op(ans), i*(i+1)]: fi od; RETURN(ans) end: ts_nsq_pronic(500);

CROSSREFS

Cf. A002378, A005117.

Sequence in context: A127026 A105962 A113695 * A280380 A184238 A285220

Adjacent sequences:  A098824 A098825 A098826 * A098828 A098829 A098830

KEYWORD

nonn

AUTHOR

Jani Melik, Oct 09 2004

STATUS

approved

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Last modified October 17 22:34 EDT 2019. Contains 328134 sequences. (Running on oeis4.)