A180597 Digital root of 7n.

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

Offset

0,2

Comments

Period of 9. - Robert G. Wilson v, Sep 20 2010

Links

Table of n, a(n) for n=0..104.

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

Formula

G.f.: x*(7 + 5*x + 3*x^2 + x^3 + 8*x^4 + 6*x^5 + 4*x^6 + 2*x^7 + 9*x^8)/(1 - x^9). - Stefano Spezia, Apr 21 2022

a(n) = A010888(A008589(n)). - Michel Marcus, Apr 21 2022

Mathematica

f[n_] := Mod[7 n - 1, 9] + 1; f[0] = 0; Array[f, 105, 0] (* Robert G. Wilson v, Sep 20 2010 *)

Prog

(PARI) a(n)=7*n%9 \\ Charles R Greathouse IV, Aug 22 2014

Crossrefs

Cf. A010888, A008589.

Cf. A180592, A180594, A180595, A180596, A180592, A180593, A180594, A180595, A180596, A180598, A180599.

Column k = 7 in A353109.

Sequence in context: A106040 A320158 A085927 * A219242 A330920 A155816

Adjacent sequences: A180594 A180595 A180596 * A180598 A180599 A180600

Keyword

easy,nonn,base

Author

Odimar Fabeny, Sep 10 2010

Extensions

More terms from Robert G. Wilson v, Sep 20 2010

Status

approved