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A077051 Right summatory matrix, T, by antidiagonals. 5
1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1 (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 row vector, then S*T is the summatory sequence of S; i.e. its n-th term is Sum{s(k): k|n}. T is the transpose of the left summatory matrix, A077049; T is the inverse of the right Moebius transformation matrix. See A077049 for further properties.

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 left summatory matrix, and A077049 the right one. [From Franklin T. Adams-Watters, Apr 08 2009]

Sum of column k is A000005. - Geoffrey Critzer, Mar 29 2015

LINKS

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

FORMULA

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

From Boris Putievskiy, May 08 2013: (Start)

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

As linear sequence a(n) =floor(A002260(n)/A004736(n)) - floor((A002260(n)-1)/A004736(n));

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

G.f. for row n: x^n/(1-x^n). - Geoffrey Critzer, Mar 29 2015

EXAMPLE

Northwest corner:

1 1 1 1 1 1

0 1 0 1 0 1

0 0 1 0 0 1

0 0 0 1 0 0

0 0 0 0 1 0

0 0 0 0 0 1

MATHEMATICA

(* returns the northwest corner *) nn = 20; Table[PadRight[Drop[CoefficientList[Series[x^n/(1 - x^n), {x, 0, nn}], x], 1], nn], {n, 1, nn}] // Grid (* Geoffrey Critzer, Mar 29 2015 *)

CROSSREFS

Cf. A077049, A077050, A077052.

Sequence in context: A131483 A077052 A133566 * A115955 A106344 A106346

Adjacent sequences:  A077048 A077049 A077050 * A077052 A077053 A077054

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Oct 22 2002

STATUS

approved

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Last modified May 29 15:03 EDT 2017. Contains 287247 sequences.