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A093449
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Least number with n distinct prime divisors arising as the product of two or more consecutive integers.
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2
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2, 6, 30, 210, 2730, 39270, 510510, 23393370, 363993630, 64790866140, 530514844860, 126408523110870, 3425113062060690, 660393717163700520, 26657280574571657010, 3448055881024876471350, 308480161111936386482910
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| 2, 6, 30, 210 and 510510 are primorials (A002110). There are no more primorials in the first 300 terms.
Upper bounds for a(14)-a(18): 660393717163700520, 28386773771493397260, 3448055881024876471350, 308480161111936386482910, 32521466098360753728404190.
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EXAMPLE
| a(7) = 510510 = 714*715 has prime divisors 2, 3, 5, 7, 11, 13 and 17.
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CROSSREFS
| Cf. A002110, A045619, A093450.
Sequence in context: A136351 A071290 A185693 * A083002 A192929 A077176
Adjacent sequences: A093446 A093447 A093448 * A093450 A093451 A093452
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KEYWORD
| hard,nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 03 2004
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EXTENSIONS
| Edited, corrected and extended by David Wasserman (dwasserm(AT)earthlink.net), Mar 21 2007
a(14)-a(17) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Sep 13 2008
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