A182437 - OEIS

%I #9 Nov 01 2017 11:33:59

%S 0,2,0,12,40,270,1848,14840,133488,1334970,14684560,176214852,

%T 2290793128,32071103750,481066556280,7697064900464,130850103307616,

%U 2355301859537394,44750735331210144,895014706624203260,18795308839108268040,413496794460381897342

%N a(0)=0, a(n) = (a(n-1) XOR n) * (n+1).

%C for n<12, a(n)=A180189(n).

%F a(0)=0, for n>0, a(n) = (a(n-1) XOR n) * (n+1).

%t nxt[{n_,a_}]:={n+1,BitXor[a,n+1](n+2)}; NestList[nxt,{0,0},30][[All,2]] (* _Harvey P. Dale_, Nov 01 2017 *)

%o (Python)

%o a=0

%o for i in range(1,55):

%o   print a,

%o   a ^= i

%o   a *= i+1

%Y Cf. A182420, A180189.

%K nonn,base

%O 0,2

%A _Alex Ratushnyak_, Apr 28 2012