A242621 - OEIS

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A242621

Start of the least triple of consecutive squarefree numbers each of which has exactly n distinct prime factors.

2, 33, 1309, 27962, 3323705, 296602730, 41704979953

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OFFSET

1,1

COMMENTS

As the example of a(4)=27962 shows, "consecutive squarefree numbers" means consecutive elements of A005117, not necessarily consecutive integers that (additionally) are squarefree; this would be a more restrictive condition.

a(8) <= 102099792179229 because A093550 - 1 is an upper bound of the present sequence.

LINKS

Table of n, a(n) for n=1..7.

Daniel C. Mayer, Define an "m-triple" to consist of three consecutive squarefree positive integers, each with exactly m prime divisors, Number Theory group on LinkedIn.com

EXAMPLE

The two squarefree numbers following a(4)=27962, namely, 27965 and 27966, also have 4 prime divisors just as a(4).

CROSSREFS

See A242605-A242608 for triples of consecutive squarefree numbers with m=2,..,5 prime factors.

See A246470 for the quadruplet and A246548 for the 5-tuple versions of this sequence.

See A039833, A066509, A176167 and A192203 for triples of consecutive numbers which are squarefree and have m=2,..,5 prime factors.

Sequence in context: A356953 A204239 A198901 * A206385 A263052 A090335

Adjacent sequences: A242618 A242619 A242620 * A242622 A242623 A242624

KEYWORD

nonn

AUTHOR

M. F. Hasler, May 18 2014

EXTENSIONS

Edited and a(6)-a(7) added by Hans Havermann, Aug 27 2014

STATUS

approved