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A061482
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a(1) = 1, a(2) = 2, a(n) = sum of products of previous terms taking n-2 at a time.
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2
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1, 2, 3, 11, 127, 16195, 262286407, 68794159432716139, 4732636372053966959311918076028751, 22397847030088134373054567592093233271179679420451463713205492138771
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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EXAMPLE
| a(3) = a(1) + a(2) = 3, a(4) = a(1)a(2) + a(2)a(3) + a(3)a(1) = 11, a(5) = 1*2*3 + 1*2*11 + 1*3*11 + 2*3*11 = 127.
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CROSSREFS
| Cf. A061902 (lengths of terms).
Sequence in context: A050721 A058114 A042337 * A177854 A135161 A066100
Adjacent sequences: A061479 A061480 A061481 * A061483 A061484 A061485
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KEYWORD
| nonn,easy
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), May 05 2001
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EXTENSIONS
| More terms from Asher Auel (asher.auel(AT)reed.edu), May 05 2001. The 11-th term has 135 digits.
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