A182537 - OEIS

A182537

a(0)=0, a(1)=1, a(n) = a(n-1) + (a(n-2) XOR n).

%I #10 Jul 02 2021 11:53:50

%S 0,1,3,5,12,12,22,33,63,103,156,264,408,669,1075,1733,2792,4540,7350,

%T 11877,19207,31095,50312,81384,131704,213097,344779,557885,902676,

%U 1460532,2363198,3823721,6186887,10010575,16197492,26208096,42405552,68613621,111019147,179632733

%N a(0)=0, a(1)=1, a(n) = a(n-1) + (a(n-2) XOR n).

%H Harvey P. Dale, <a href="/A182537/b182537.txt">Table of n, a(n) for n = 0..1000</a>

%F a(0)=0, a(1)=1, a(n) = a(n-1) + (a(n-2) XOR n), where XOR is the bitwise exclusive-or operator.

%t nxt[{n_,a_,b_}]:={n+1,b,b+BitXor[a,n+1]}; NestList[nxt,{1,0,1},40][[All,2]] (* _Harvey P. Dale_, Jul 02 2021 *)

%o (Python)

%o prpr, prev = 0, 1

%o for n in range(2, 99):

%o . current = prev + (prpr ^ n)

%o . print prpr,

%o . prpr, prev = prev, current

%Y Cf. A182509, A182536.

%K nonn,base,easy

%O 0,3

%A _Alex Ratushnyak_, May 04 2012