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A081978
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Smallest triangular number with n divisors, or 0 if no such number exists.
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1
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1, 3, 0, 6, 0, 28, 0, 66, 36, 496, 0, 276, 0, 378, 1631432881, 120, 0, 300, 0
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(p)=0 if p is an odd prime. If n is an odd composite number, then a(n) is a square; see A001110 for numbers that are both triangular and square. - Victoria Sapko (vsapko(AT)frc.mass.edu), Sep 28 2007
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EXAMPLE
| a(2)=3 because the smallest triangular number with 2 divisors is T(2)=3.
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CROSSREFS
| Cf. A081979.
Cf. A001110.
Sequence in context: A007386 A007385 A022899 * A117784 A197807 A111074
Adjacent sequences: A081975 A081976 A081977 * A081979 A081980 A081981
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KEYWORD
| more,nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 03 2003
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EXTENSIONS
| More terms from Victoria Sapko (vsapko(AT)frc.mass.edu), Sep 28 2007
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