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A055248 Triangle of partial row sums of triangle A007318(n,m) (Pascal's triangle). Triangle A008949 read backwards. 23
1, 2, 1, 4, 3, 1, 8, 7, 4, 1, 16, 15, 11, 5, 1, 32, 31, 26, 16, 6, 1, 64, 63, 57, 42, 22, 7, 1, 128, 127, 120, 99, 64, 29, 8, 1, 256, 255, 247, 219, 163, 93, 37, 9, 1, 512, 511, 502, 466, 382, 256, 130, 46, 10, 1, 1024, 1023, 1013, 968, 848, 638, 386, 176, 56, 11, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

In the language of the Shapiro et al. reference (given in A053121) such a lower triangular (ordinary) convolution array, considered as matrix, belongs to the Riordan-group. The G.f. for the row polynomials p(n,x) (increasing powers of x) is 1/((1-2*z)*(1-x*z/(1-z))).

a(n,m) = A008949(n,n-m), if n>m >= 0.

Binomial transform of the all 1's triangle: as a Riordan array, it factors to give (1/(1-x),x/(1-x))(1/(1-x),x). Viewed as a number square read by anti-diagonals, it has T(n,k)=sum{j=0..n, C(n+k,n-j)} and is then the binomial transform of the Whitney square A004070. - Paul Barry (pbarry(AT)wit.ie), Feb 03 2005

Riordan array (1/(1-2x), x/(1-x)). Diagonal sums are A027934. - Paul Barry (pbarry(AT)wit.ie), Jan 30 2005

Eigensequence of the triangle = A005493: (1, 3, 10, 37, 151, 674,...); row sums of triangles A011971 and A159573. [From Gary W. Adamson (qntmpkt(AT)yahoo.com), Apr 16 2009]

FORMULA

a(n, m)=sum(A007318(n, k), k=m..n), (partial row sums in columns m).

Column m recursion: a(n, m)= sum(a(j, m), j=m..n-1)+ A007318(n, m) if n >= m >= 0, a(n, m) := 0 if n<m.

G.f. for column m: (1/(1-2*x))*(x/(1-x))^m, m >= 0.

T(n, k)=sum{j=0..n, binomial(n, k+j)}. - Paul Barry (pbarry(AT)wit.ie), Jan 30 2005

a(n, m)=sum{j=0..n, binomial(n, m+j)} - Paul Barry (pbarry(AT)wit.ie), Feb 03 2005

Inverse binomial transform (by columns) of A112626. - Ross La Haye (rlahaye(AT)new.rr.com), Dec 31 2006

T(2n,n)=A032443(n). [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 16 2009]

EXAMPLE

{1}; {2,1}; {4,3,1}; {8,7,4,1};...

Fourth row polynomial (n=3): p(3,x)= 8+7*x+4*x^2+x^3

CROSSREFS

Cf. A008949, A007318. Column sequences: A000079 (powers of 2), A000225, A000295, A002662-4, A035038-42 for m=0..10, Row sums: A001792(n) = A055249(n, 0).

A011971, A159573 [From Gary W. Adamson (qntmpkt(AT)yahoo.com), Apr 16 2009]

Sequence in context: A109435 A134392 A048483 * A103316 A140069 A105851

Adjacent sequences:  A055245 A055246 A055247 * A055249 A055250 A055251

KEYWORD

easy,nonn,tabl

AUTHOR

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de), May 26 2000

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Last modified February 17 14:12 EST 2012. Contains 206031 sequences.