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

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A152571 Triangle T(n,k) read by rows: T(n,n) = -1, T(n,0) = 4^(n - 1), T(n,k) = -4^(n - k - 1), 1 <= k <= n - 1. 4
 -1, 1, -1, 4, -1, -1, 16, -4, -1, -1, 64, -16, -4, -1, -1, 256, -64, -16, -4, -1, -1, 1024, -256, -64, -16, -4, -1, -1, 4096, -1024, -256, -64, -16, -4, -1, -1, 16384, -4096, -1024, -256, -64, -16, -4, -1, -1, 65536, -16384, -4096, -1024, -256, -64, -16, -4, -1, -1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS FORMULA From Franck Maminirina Ramaharo, Jan 08 2019: (Start) G.f.: -(1 - 5*y + 2*x*y^2)/(1 - (4 + x)*y + 4*x*y^2). E.g.f.: -(4 - x - (2 - x)*exp(4*y) + (6 - 2*x)*exp(x*y))/(8 - 2*x). (End) EXAMPLE Triangle begins:       -1;        1,     -1;        4,     -1,     -1;       16,     -4,     -1,    -1;       64,    -16,     -4,    -1,    -1;      256,    -64,    -16,    -4,    -1,   -1;     1024,   -256,    -64,   -16,    -4,   -1,  -1;     4096,  -1024,   -256,   -64,   -16,   -4,  -1,  -1;    16384,  -4096,  -1024,  -256,   -64,  -16,  -4,  -1, -1;    65536, -16384,  -4096, -1024,  -256,  -64, -16,  -4, -1, -1;   262144, -65536, -16384, -4096, -1024, -256, -64, -16, -4, -1, -1;      ... MATHEMATICA b[0] = {-1}; b[1] = {1, -1}; b[n_] := b[n] = Join[{4^(n - 1)}, {-b[n - 1][[1]]}, Table[b[n - 1][[i]], {i, 2, Length[b[n - 1]]}]]; Flatten[Table[b[n], {n, 0, 10}]] PROG (Maxima) T(n, k) := if k = n then -1 else if k = 0 then 4^(n - 1) else -4^(n - k - 1)\$ create_list(T(n, k), n, 0, 20, k, 0, n); /* Franck Maminirina Ramaharo, Jan 08 2019 */ CROSSREFS Row sums (except row 0): A020988. Cf. A057728, A152568, A152570, A152572. Sequence in context: A116469 A156599 A010320 * A008304 A203846 A118185 Adjacent sequences:  A152568 A152569 A152570 * A152572 A152573 A152574 KEYWORD sign,easy,tabl AUTHOR Roger L. Bagula, Dec 08 2008 EXTENSIONS Edited by Franck Maminirina Ramaharo, Jan 08 2019 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 December 8 14:18 EST 2021. Contains 349596 sequences. (Running on oeis4.)