A182537 a(0)=0, a(1)=1, a(n) = a(n-1) + (a(n-2) XOR n).

0, 1, 3, 5, 12, 12, 22, 33, 63, 103, 156, 264, 408, 669, 1075, 1733, 2792, 4540, 7350, 11877, 19207, 31095, 50312, 81384, 131704, 213097, 344779, 557885, 902676, 1460532, 2363198, 3823721, 6186887, 10010575, 16197492, 26208096, 42405552, 68613621, 111019147, 179632733

Offset: 0

Author

Alex Ratushnyak, May 04 2012

Keywords

• nonn
• base
• easy

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A182509, A182536.

Programs

Mathematica

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 *)

Python

prpr, prev = 0, 1
for n in range(2, 99):
  current = prev + (prpr ^ n)
  print(prpr, end=', ')
  prpr, prev = prev, current

Formula

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