The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A235501 Riordan array (1/(1-2*x^2), x/(1-x)). 0
 1, 0, 1, 2, 1, 1, 0, 3, 2, 1, 4, 3, 5, 3, 1, 0, 7, 8, 8, 4, 1, 8, 7, 15, 16, 12, 5, 1, 0, 15, 22, 31, 28, 17, 6, 1, 16, 15, 37, 53, 59, 45, 23, 7, 1, 0, 31, 52, 90, 112, 104, 68, 30, 8, 1, 32, 31, 83, 142, 202, 216, 172, 98, 38, 9, 1, 0, 63, 114, 225 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Row sums are A007179(n+1). LINKS FORMULA T(n,n)=1, T(2n,0)=2^n, T(2n+1,0)=0, T(n,k)=T(n-1,k-1)+T(n-1,k) for 0n. T(n,n)=1, T(n+1,n)=n, T(n+2,n)=n*(n+1)/2 + 2. exp(x) * e.g.f. for row n = e.g.f. for diagonal n. For example, for n = 3 we have exp(x)*(3*x + 2*x^2/2! + x^3/3!) = 3*x + 8*x^2/2! + 16*x^3/3! + 28*x^4/4! + 45*x^5/5! + .... The same property holds more generally for Riordan arrays of the form ( f(x), x/(1 - x) ). - Peter Bala, Dec 22 2014 EXAMPLE Triangle begins (0<=k<=n): 1 0, 1 2, 1, 1 0, 3, 2, 1 4, 3, 5, 3, 1 0, 7, 8, 8, 4, 1 8, 7, 15, 16, 12, 5, 1 0, 15, 22, 31, 28, 17, 6, 1 CROSSREFS Cf. Columns: A077957, A052551, A077866. Diagonals: A000012, A001477, A022856. Cf. Similar sequences: A059260, A191582. Sequence in context: A029340 A288166 A126258 * A116382 A050606 A277721 Adjacent sequences:  A235498 A235499 A235500 * A235502 A235503 A235504 KEYWORD nonn,easy,tabl AUTHOR Philippe Deléham, Jan 11 2014 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 14 01:55 EDT 2020. Contains 336476 sequences. (Running on oeis4.)