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A077049 Left summatory matrix, T, by antidiagonals. 13
1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If S=(s(1),s(2),...) is a sequence written as a column vector, then T*S is the summatory sequence of S; i.e. its n-th term is Sum{s(k): k|n}. T is the inverse of the left Moebius transformation matrix, A077050. Except for the first term in some cases, Column 1 of T^(-2) is A007427, Column 1 of T^(-1) is A008683, Column 1 of T^2 is A000005, Column 1 of T^3 is A007425.

This is essentially the same as A051731, which includes only the triangle. Note that the standard in the OEIS is left to right antidiagonals, which would make this the right summatory matrix, and A077051 the left one. [Franklin T. Adams-Watters, Apr 08 2009]

From Gary W. Adamson, Apr 28 2010: (Start)

As defined with antidiagonals of the array = the triangle shown in the example section. Row sums of this triangle = A032741 (with a different offset): 1, 1, 2, 1, 3, 1, 3,...

Let the triangle = M. Then Lim_{n-inf} M^n = A002033, the left-shifted vector considered as a sequence: (1, 1, 1, 2, 1, 3, 1, 4, 2, 3, 1, 8,...). (End)

LINKS

Table of n, a(n) for n=1..105.

C. Kimberling, Matrix Transformations of Integer Sequences, J. Integer Seqs., Vol. 6, 2003.

FORMULA

T(n, k)=1 if k|n, else T(n, k)=0, k>=1, n>=1.

From Boris Putievskiy, May 08 2013: (Start)

As table T(n,k) =  floor(k/n)-floor((k-1)/n).

As linear sequence a(n) = floor(A004736(n)/A002260(n)) - floor((A004736(n)-1)/A002260(n)); a(n) = floor(j/i)-floor((j-1)/i), where i=n-t*(t+1)/2, j=(t*t+3*t+4)/2-n, t=floor((-1+sqrt(8*n-7))/2). (End)

EXAMPLE

T(4,2)=1 since 2 divides 4. Northwest corner:

1 0 0 0 0 0

1 1 0 0 0 0

1 0 1 0 0 0

1 1 0 1 0 0

1 0 0 0 1 0

1 1 1 0 0 1

From Gary W. Adamson, Apr 28 2010: (Start)

First few rows of the triangle =

1;

1, 0;

1, 1, 0;

1, 0, 0, 0;

1, 1, 1, 0, 0;

1, 0, 0, 0, 0, 0;

1, 1, 0, 1, 0, 0, 0;

1, 0, 1, 0, 0, 0, 0, 0;

1, 1, 0, 0, 1, 0, 0, 0, 0;

... (End)

PROG

(PARI) nn=10; matrix(nn, nn, n, k, if (n % k, 0, 1)) \\ Michel Marcus, May 21 2015

CROSSREFS

Cf. A077050, A077051, A077052.

Cf. A032741, A002033. [Gary W. Adamson, Apr 28 2010]

Sequence in context: A014577 A157926 A131377 * A124895 A089885 A143242

Adjacent sequences:  A077046 A077047 A077048 * A077050 A077051 A077052

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Oct 22 2002

STATUS

approved

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Last modified March 26 00:51 EDT 2017. Contains 284111 sequences.