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A071919 Number of monotone nondecreasing functions [n]->[m] for n>=0, m>=0, read by antidiagonals. 11
1, 1, 0, 1, 1, 0, 1, 2, 1, 0, 1, 3, 3, 1, 0, 1, 4, 6, 4, 1, 0, 1, 5, 10, 10, 5, 1, 0, 1, 6, 15, 20, 15, 6, 1, 0, 1, 7, 21, 35, 35, 21, 7, 1, 0, 1, 8, 28, 56, 70, 56, 28, 8, 1, 0, 1, 9, 36, 84, 126, 126, 84, 36, 9, 1, 0, 1, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1, 0, 1, 11, 55, 165, 330, 462 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,8

COMMENTS

Sometimes called a Riordan array.

Number of different partial sums of 1+[2,3]+[3,4]+[4,5]+... - Jon Perry, Jan 01 2004

Triangle T(n,k), 0<=k<=n, read by rows, given by [1, 0, 0, 0, 0, 0, 0, 0, ...] DELTA [0, 1, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938 . - Philippe DELEHAM, Sep 05 2005

T(n,k)=abs(A110555(n,k)), A110555(n,k)=T(n,k)*(-1)^k. - Reinhard Zumkeller, Jul 27 2005

(1,0)-Pascal triangle . - Philippe DELEHAM, Nov 21 2006

A129186*A007318 as infinite lower triangular matrices. [From Philippe DELEHAM, Mar 07 2009]

Let n>=0 index the rows and m>=0 index the columns of this rectangular array. R(n,m) is "m multichoose n", the number of multisets of length n on m symbols. R(n,m)= Sum_i=0...n;R(i,m-1). The summation conditions on the number of members in a size n multiset that are not the element m (an arbitrary element in the set of m symbols). R(n,m)= Sum_i=1...m;R(n-1,i). The summation conditions on the largest element in a size n multiset on {1,2,...m}. [From Geoffrey Critzer, Jun 03 2009]

Sum(T(n,k)*B(k),k=0..n) = B(n), n>=0, with the Bell numbers B(n):=A000110(n) (eigensequence). See e.g., the W. Lang link, Corollary 4. [From Wolfdieter Lang, Jun 23 2010]

REFERENCES

D. Merlini, F. Uncini and M. C. Verri, A unified approach to the study of general and palindromic compositions, Integers 4 (2004), A23, 26 pp.

LINKS

Table of n, a(n) for n=0..83.

Wolfdieter Lang, Simple proofs of some facts related to the Bell sequence and triangles A007318 (Pascal) and A071919 (enlarged Pascal). [From Wolfdieter Lang, Jun 23 2010]

FORMULA

Lim_{k->inf.} A071919^k = (A000110,0,0,0,0,...) with the Bell numbers in the first column. For a proof see, e.g., the W. Lang link, proposition 12.

T(n, k)=1 if (n, k)=(0, 0), a(n, k)=binomial(n+k-1, n) otherwise. - Reinhard Zumkeller, Jul 27 2005

G.f.: 1 +x +x^3(1+x) +x^6(1+x)^2 +x^10(1+x)^3 +... . - Michael Somos Aug 20 2006

MATHEMATICA

Table[Table[Binomial[m - 1 + n, n], {m, 0, 10}], {n, 0, 10}] // Grid [From Geoffrey Critzer, Jun 03 2009]

PROG

(PARI) { n=20; v=vector(n); for (i=1, n, v[i]=vector(2^(i-1))); v[1][1]=1; for (i=2, n, k=length(v[i-1]); for (j=1, k, v[i][j]=v[i-1][j]+i; v[i][j+k]=v[i-1][j]+i+1)); c=vector(n); for (i=1, n, for (j=1, 2^(i-1), if (v[i][j]<=n, c[v[i][j]]++))); c } (Jon Perry)

(PARI) {a(n)=local(m); if(n<1, n==0, m=(sqrtint(8*n+1)-1)\2; binomial(m-1, n-m*(m+1)/2))} /* Michael Somos Aug 20 2006 */

CROSSREFS

A000110 [From Gary W. Adamson, Jan 02 2009]

Sequence in context: A213889 A110555 * A097805 A167763 A127839 A017827

Adjacent sequences:  A071916 A071917 A071918 * A071920 A071921 A071922

KEYWORD

nonn,easy,tabl

AUTHOR

Michele Dondi (bik.mido(AT)tiscalinet.it), Jun 14, 2002

EXTENSIONS

More terms from Reinhard Zumkeller, Jul 27 2005

STATUS

approved

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Last modified May 18 21:01 EDT 2013. Contains 225428 sequences.