This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A171501 Inverse binomial transform of A084640. 1
 0, 1, 3, -1, 7, -9, 23, -41, 87, -169, 343, -681, 1367, -2729, 5463, -10921, 21847, -43689, 87383, -174761, 349527, -699049, 1398103, -2796201, 5592407, -11184809, 22369623, -44739241, 89478487, -178956969, 357913943, -715827881 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS a(n) and differences are 0,     1,   3,  -1,    7,   -9, 1,     2,  -4,   8,  -16,   32,  =(-1)^(n+1) * A171449(n), 1,    -6,  12, -24,   48,  -96, -7,   18, -36,  72, -144,  288, 25,  -54, 108, -216, 432, -864, Vertical: 1) 0 followed with A168589(n).           2) (-1 followed with A008776(n) ) signed. See A025192(n). Main diagonal: see A167747(1+n). - Paul Curtz, Jun 16 2011 LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (-1,2) FORMULA a(n) = A140966(n), n>0. G.f.: x*(1+4*x) / ( (1+2*x)*(1-x) ). - R. J. Mathar, Jun 14 2011 a(1+n)= (-1)^(1+n) * A001045(1+n) + 2. - Paul Curtz Jun 16 2011 MATHEMATICA CoefficientList[Series[x*(1 + 4*x)/((1 + 2*x)*(1 - x)), {x, 0, 30}], x] PROG (MAGMA) I:=[0, 1, 3]; [n le 3 select I[n] else -Self(n-1) + 2*Self(n-2): n in [1..40]]; // Vincenzo Librandi, Oct 18 2012 CROSSREFS Sequence in context: A011308 A033465 A096431 * A280332 A279939 A286511 Adjacent sequences:  A171498 A171499 A171500 * A171502 A171503 A171504 KEYWORD easy,sign AUTHOR Paul Curtz, Dec 10 2009 EXTENSIONS Mathematica program by Olivier Gérard, Jul 06 2011 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 September 15 14:38 EDT 2019. Contains 327078 sequences. (Running on oeis4.)