A237054 a(1)=1, a(n) = (a(n-1) + n) XOR n.

1, 1, 7, 15, 17, 17, 31, 47, 49, 49, 55, 79, 81, 81, 111, 111, 145, 177, 215, 255, 257, 257, 271, 319, 321, 321, 327, 383, 385, 385, 447, 511, 513, 513, 519, 527, 529, 529, 543, 623, 689, 753, 823, 847, 849, 849, 943, 1007, 1041, 1137, 1175, 1279, 1281, 1281

Offset: 1

Author

Alex Ratushnyak, Feb 03 2014

Keywords

• nonn
• easy

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A182389, A182242.

Programs

Mathematica

Module[{n = 1}, NestList[BitXor[++n, # + n] &, 1, 100]] (* Paolo Xausa, Nov 26 2024 *)

Python

a=1
for n in range(2, 77):
  print(a, end=', ')
  a = (a+n) ^ n

Formula

a(1)=1, then a(n) = (a(n-1) + n) XOR n, where XOR is the bitwise exclusive-OR operator.