Search: id:A067998 Results 1-1 of 1 results found. %I A067998 %S A067998 0,1,0,3,8,15,24,35,48,63,80,99,120,143,168,195,224,255,288,323,360,399, 440,483,528, %T A067998 575,624,675,728,783,840,899,960,1023,1088,1155,1224,1295,1368,1443,1520, 1599,1680, %U A067998 1763,1848,1935,2024,2115,2208,2303,2400,2499,2600,2703,2808,2915,3024, 3135,3248,3363 %V A067998 0,-1,0,3,8,15,24,35,48,63,80,99,120,143,168,195,224,255,288,323,360,399, 440,483,528, %W A067998 575,624,675,728,783,840,899,960,1023,1088,1155,1224,1295,1368,1443,1520, 1599,1680, %X A067998 1763,1848,1935,2024,2115,2208,2303,2400,2499,2600,2703,2808,2915,3024, 3135,3248,3363 %N A067998 n^2 - 2*n. %F A067998 a(n) = A005563(n-2) = A005563(-n) = A000290(n-1)-1 %F A067998 G.f.: x(3x-1)/(1-x)^3; E.g.f.: e^x(x^2-x); - Paul Barry (pbarry(AT)wit.ie), Mar 27 2007 %F A067998 a(n)=2*n+a(n-1)-5 (with a(1)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 08 2009] %e A067998 For n=2, a(2)=2*2+0-5=-1; n=3, a(3)=2*3-1-5=0; n=4, a(4)=2*4+0-5=3 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 08 2009] %p A067998 a:=n->sum(binomial(n,1),j=3..n): seq(a(n), n=0..59); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Feb 12 2007 %p A067998 a[0]:=0:a[1]:=1:for n from 2 to 63 do a[n]:=2*a[n-1]-a[n-2]-2 od: seq(-a[n], n=1..63); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Feb 18 2008 %p A067998 with(combinat, fibonacci):seq(fibonacci(3, i)-2,i=-1..58); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 20 2008 %t A067998 Table[ n^2 - 2*n, {n, 0, 60} ] %Y A067998 Essentially the same as A005563. %Y A067998 Sequence in context: A132411 A147998 A164003 this_sequence A060615 A022451 A080181 %Y A067998 Adjacent sequences: A067995 A067996 A067997 this_sequence A067999 A068000 A068001 %K A067998 easy,sign,new %O A067998 0,4 %A A067998 George E. Antoniou (george.antoniou(AT)montclair.edu), Feb 06 2002 %E A067998 Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 08 2002 Search completed in 0.001 seconds