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A071977
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Triangle in which first row is {1}; to get n-th row take first n numbers greater than last number in previous row which are relatively prime to n.
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4
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1, 3, 5, 7, 8, 10, 11, 13, 15, 17, 18, 19, 21, 22, 23, 25, 29, 31, 35, 37, 41, 43, 44, 45, 46, 47, 48, 50, 51, 53, 55, 57, 59, 61, 63, 65, 67, 68, 70, 71, 73, 74, 76, 77, 79, 81, 83, 87, 89, 91, 93, 97, 99, 101, 103, 104, 105, 106, 107, 108, 109, 111, 112, 113, 114, 115
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Reinhard Zumkeller, Rows n=1..120 of triangle, flattened
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EXAMPLE
| Triangle begins 1; 3 5; 7 8 10; 11 13 15 17; 18 19 21 22 23; 25 29 31 35 37 41; ....
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MATHEMATICA
| a = {1}; k = 2; Do[i = 1; While[i < n + 1, If[ GCD[k, n] == 1, a = Append[a, k]; i++ ]; k++ ], {n, 2, 12}]; a
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PROG
| (Haskell)
a071977 n k = a071977_tabl !! (n-1) !! (k-1)
a071977_row n = a071977_tabl !! (n-1)
a071977_tabl = f 1 [1..] where
f k xs = ys : f (k+1) (dropWhile (<= last ys) xs) where
ys = take k $ filter ((== 1) . (gcd k)) xs
-- Reinhard Zumkeller, Jan 18 2012
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CROSSREFS
| Diagonals give A071978, A071979.
A033291.
Sequence in context: A171508 A049068 A185602 * A183423 A109404 A186342
Adjacent sequences: A071974 A071975 A071976 * A071978 A071979 A071980
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KEYWORD
| nonn,tabl
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jun 18 2002
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EXTENSIONS
| Edited by Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 28 2002
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