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A112599 Triangle where a(1,1) = 1, a(n,m) = number of terms of row (n-1) which are coprime to m. 4
1, 1, 1, 2, 2, 2, 3, 0, 3, 0, 4, 2, 0, 2, 2, 5, 0, 4, 0, 4, 0, 6, 1, 3, 1, 2, 1, 3, 7, 5, 4, 5, 7, 3, 7, 5, 8, 7, 7, 7, 5, 6, 5, 7, 7, 9, 7, 8, 7, 7, 7, 4, 7, 8, 5, 10, 7, 9, 7, 9, 6, 5, 7, 9, 6, 10, 11, 7, 6, 7, 8, 4, 8, 7, 6, 6, 11, 4, 12, 5, 9, 5, 12, 5, 9, 5, 9, 5, 10, 5, 12, 13, 9, 7, 9, 6, 6, 13, 9, 7 (list; table; graph; refs; listen; history; 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.

EXAMPLE

Row 6 of the triangle is [5,0,4,0,4,0]. Among these terms there are 6 terms coprime to 1, 1 term coprime to 2, 3 terms coprime to 3, 1 term coprime to 4, 2 terms coprime to 5, 1 term coprime to 6 and 3 terms coprime to 7. So row 7 is [6,1,3,1,2,1,3].

1

1 1

2 2 2

3 0 3 0

4 2 0 2 2

5 0 4 0 4 0

6 1 3 1 2 1 3

7 5 4 5 7 3 7 5

8 7 7 7 5 6 5 7 7

9 7 8 7 7 7 4 7 8 5

MATHEMATICA

f[l_] := Block[{p, t}, p = l[[ -1]]; k = Length[p]; t = Table[ Sum[ If[GCD[p[[j]], n] == 1, 1, 0], {j, k}], {n, k + 1}]; Return[Append[l, t]]; ]; Flatten[Nest[f, {{1}}, 13]] (*Chandler*)

CROSSREFS

Row sums are in A114718. [From Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Jun 01 2009]

Sequence in context: A035307 A004481 A004489 * A106795 A162203 A071455

Adjacent sequences:  A112596 A112597 A112598 * A112600 A112601 A112602

KEYWORD

nonn,tabl

AUTHOR

Leroy Quet Dec 21 2005

EXTENSIONS

Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Dec 24 2005

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Last modified February 15 19:15 EST 2012. Contains 205852 sequences.