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A027430
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Number of distinct products ijk with 1 <= i<j<k <= n.
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17
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0, 0, 1, 4, 10, 16, 29, 42, 60, 75, 111, 126, 177, 206, 238, 274, 361, 396, 507, 554, 613, 677, 838, 883, 1004, 1092, 1198, 1277, 1529, 1590, 1881, 1998, 2133, 2275, 2432, 2518, 2921, 3096, 3278, 3391, 3884, 4014, 4563, 4750, 4938, 5186, 5840, 5987, 6422, 6652
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,4
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REFERENCES
| Amarnath Murthy, Generalization of partition function introducing Smarandache Factor Partitions, Smarandache Notions Journal, 1-2-3, Vol. 11, 2000.
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..200
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FORMULA
| a(n)=A027429(n)-1. - T. D. Noe, Jan 16 2007
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PROG
| (Haskell)
import Data.List (nub)
a027430 n = length $ nub [i*j*k | k<-[3..n], j<-[2..k-1], i<-[1..j-1]]
-- Reinhard Zumkeller, Jan 01 2012
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CROSSREFS
| Cf. A027425, A100435, A100436.
Number of terms in row n of A083507.
Cf. A027429, A027428.
Sequence in context: A191115 A073121 A167346 * A027425 A024992 A069982
Adjacent sequences: A027427 A027428 A027429 * A027431 A027432 A027433
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KEYWORD
| nonn
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| Corrected by David Wasserman (wasserma(AT)spawar.navy.mil), Nov 18 2004
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