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A147831
Minimum number k for which the digital sum of k*n is 11*n.
9
0, 29, 299, 2333, 49997, 1199999, 8333333, 99999857, 2499999986, 11111111111, 2999999999999, 29090909090909, 74999999999999, 1523076923076923, 27857142857142857, 533333333333333333, 5624999999999999993, 52940588235294117647, 1111111111111111111111, 21052631578947368368421
OFFSET
0,2
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=11*n then ok:=0; print(j); fi; od; od; end: P(100);
PROG
(PARI) a(n) = {my(k = 0); while (sumdigits(k*n) != 11*n, k++); k; }; \\ Michel Marcus, Mar 21 2016
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
EXTENSIONS
Edited by Charles R Greathouse IV, Nov 01 2009
a(6)-a(9) from Donovan Johnson, Sep 16 2012
a(10)-a(19) from Chai Wah Wu, Mar 20 2016
STATUS
approved