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A112592 Triangle where a(1,1) = 0, a(n,m) = number of terms of row (n-1) which are coprime to m. 3
0, 1, 0, 2, 1, 1, 3, 2, 3, 2, 4, 2, 2, 2, 4, 5, 0, 5, 0, 5, 0, 6, 3, 3, 3, 0, 3, 3, 7, 5, 0, 5, 6, 0, 6, 5, 8, 4, 4, 4, 3, 4, 5, 4, 4, 9, 2, 8, 2, 8, 1, 9, 2, 8, 1, 10, 4, 8, 4, 10, 2, 10, 4, 8, 4, 10, 11, 0, 11, 0, 7, 0, 11, 0, 11, 0, 11, 0, 12, 6, 6, 6, 6, 6, 5, 6, 6, 6, 1, 6, 6, 13, 2, 2, 2, 12, 2, 13, 2 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,4
COMMENTS
GCD(m,0) is considered here to be m, so 0 is coprime to no positive integer but 1.
LINKS
Diana Mecum, Table of n, a(n) for n = 1..2000 [From Diana L. Mecum, Aug 12 2008]
EXAMPLE
Row 6 of the triangle is [5,0,5,0,5,0]. Among these terms there are 6 terms coprime to 1, 3 terms coprime to 2, 3 terms coprime to 3, 3 terms coprime to 4, 0 terms coprime to 5, 3 terms coprime to 6 and 3 terms coprime to 7. So row 7 is [6,3,3,3,0,3,3].
0,
1,0,
2,1,1,
3,2,3,2,
4,2,2,2,4,
5,0,5,0,5,0,
6,3,3,3,0,3,3,
7,5,0,5,6,0,6,5,
8,4,4,4,3,4,5,4,4
MATHEMATICA
f[l_] := Block[{p, t}, p = l[[ -1]]; k = Length@p; t = Table[Count[GCD[p, n], 1], {n, k + 1}]; Return@Append[l, t]; ]; Nest[f, {{0}}, 13] // Flatten (* Robert G. Wilson v *)
CROSSREFS
Cf. A112599.
Row sums are in A114719. [From Klaus Brockhaus, Jun 01 2009]
Sequence in context: A060117 A196526 A234504 * A370666 A351466 A070036
KEYWORD
nonn,tabl
AUTHOR
Leroy Quet, Dec 24 2005
EXTENSIONS
More terms from Robert G. Wilson v, Dec 27 2005
Terms a(100) through a(2000) from Diana L. Mecum, Aug 12 2008
STATUS
approved

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Last modified March 29 09:59 EDT 2024. Contains 371268 sequences. (Running on oeis4.)