A144468 Final digit of multiples of 7.

0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0, 7, 4, 1, 8, 5

Offset: 0

Author

Paul Curtz, Oct 09 2008

Keywords

• nonn
• easy
• base

Comments

Period 10: repeat [0, 7, 4, 1, 8, 5, 2, 9, 6, 3]. The ten digits by jumps of three terms or a(3n). Also reverse of A131579(n+1), n =1..10, repeated.

Links

• Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,1).

Crossrefs

Cf. A131579.

Programs

Mathematica

Table[Last[IntegerDigits[7n]], {n, 0, 98}] (* Alonso del Arte, Feb 06 2014 *)
Mod[7*Range[0,100],10] (* or *) PadRight[{},100,{0,7,4,1,8,5,2,9,6,3}] (* Harvey P. Dale, Jul 28 2017 *)

PARI

a(n)=7*n%10 \\ Charles R Greathouse IV, Jun 02 2011

Formula

a(n) = 7*n (mod 10) = -3*n (mod 10), n >= 0. See the name.

a(n+10) = a(n). - Wesley Ivan Hurt, Apr 16 2024