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A137895 Products of two or more consecutive numbers such that these products do not have prime gaps in their factorizations. 2
2, 6, 12, 24, 30, 60, 72, 90, 120, 210, 240, 360, 420, 600, 720, 840, 1260, 1680, 2520, 3360, 5040, 6480, 6720, 9240, 15120, 15750, 20160, 30240, 40320, 50400, 55440, 60480, 117600, 147840, 151200, 166320, 181440, 194040, 240240, 291060, 332640 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A045619 and A073491; A000142 is a subsequence apart from initial terms.

LINKS

Table of n, a(n) for n=1..41.

EXAMPLE

a(10) = 210 = 2 * 3 * 5 * 7 = 5 * (5+1) * (5+2);

a(11) = 240 = 2^4 * 3 * 5 = 15 * (15+1);

a(12) = 360 = 2^3 * 3^2 * 5 = 3 * (3+1) * (3+2) * (3+3);

a(13) = 420 = 2^2 * 3 * 5 * 7 = 20 * (20+1);

a(14) = 600 = 2^3 * 3 * 5^2 = 24 * (24+1);

a(15) = 720 = 2^4 * 3^2 * 5 = 6!.

CROSSREFS

Sequence in context: A244043 A058868 A129314 * A194096 A099993 A011778

Adjacent sequences:  A137892 A137893 A137894 * A137896 A137897 A137898

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Feb 20 2008

STATUS

approved

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Last modified July 23 19:33 EDT 2019. Contains 325263 sequences. (Running on oeis4.)