A147828 Minimum number k for which the digital sum of k*n is 8*n.

0, 8, 44, 233, 1997, 17999, 83333, 571427, 6249986, 11111111, 899999999, 809090909, 7499999999, 53846076923, 492857142857, 5333333333333, 37499999999993, 176470588235294, 1111111111111111, 5263157894736842, 449999999999999999, 423809047619047619, 3590909090909090909

Offset

0,2

Links

Chai Wah Wu, Table of n, a(n) for n = 0..29

Maple

P:=proc(i) local j, k, n, ok, w; for n from 0 by 1 to i do j:=-1; ok:=1; while ok=1 do j:=j+1; w:=0; k:=n*j; while k>0 do w:=w+k-(trunc(k/10)*10); k:=trunc(k/10); od; if w=8*n then ok:=0; print(j); fi; od; od; end: P(100);

Prog

(PARI) a(n) = {my(k = 0); while (sumdigits(k*n) != 8*n, k++); k; }; \\ Michel Marcus, Mar 21 2016

Crossrefs

Cf. A147822-A147827, A147829-A147831.

Sequence in context: A082762 A249794 A322498 * A155604 A126476 A220629

Adjacent sequences: A147825 A147826 A147827 * A147829 A147830 A147831

Keyword

easy,nonn,base

Author

Paolo P. Lava and Giorgio Balzarotti, Nov 14 2008

Extensions

Edited by Charles R Greathouse IV, Nov 01 2009

a(8)-a(14) from Donovan Johnson, Sep 16 2012

a(14) corrected and a(15)-a(22) added by Chai Wah Wu, Mar 20 2016

Status

approved