A203601 a(0)=1, a(n+1) = (a(n)*7) XOR a(n).

1, 6, 44, 280, 1712, 10336, 78528, 610688, 4745984, 28476928, 173222912, 1108678656, 6652604416, 48774012928, 292681859072, 1757200613376, 11780162781184, 70685271916544, 424730711293952, 3116299774853120, 19823698692276224, 120070359807426560, 720738827865423872

Offset: 0

Author

Alex Ratushnyak, May 06 2012

Keywords

• nonn
• base
• easy

Comments

A007814(a(n))=n. - Robert Israel, Mar 22 2020

Links

• Robert Israel, Table of n, a(n) for n = 0..1220

Crossrefs

Cf. A001317: a(n+1) = (a(n)*2) XOR a(n).

Cf. A038183: a(n+1) = (a(n)*4) XOR a(n).

Cf. A182556: a(n+1) = (a(n)*6) XOR a(n).

Cf. A100311: a(n+1) = (a(n)*8) XOR a(n).

Cf. A007814.

Programs

Maple

a[0]:= 1:
for i from 1 to 50 do a[i]:= Bits:-Xor(a[i-1],a[i-1]*7) od:
seq(a[i],i=0..50); # Robert Israel, Mar 22 2020

Python

a=1
for n in range(55):
    print(a, end=',')
    a ^= a*7

Formula

a(0)=1, a(n+1) = (a(n)*7) XOR a(n), where XOR is the bitwise exclusive-or operator.