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A232184
Let x(0)x(1)x(2)... x(q) denote the decimal expansion of n. Sequence lists the numbers n > 10 such that x(0)/x(1)x(2)... x(q) + x(0)x(1)/x(2)x(3)... x(q) + ... + x(0)x(1)... x(q-1)/x(q) is an integer.
1
11, 21, 22, 31, 33, 41, 42, 44, 51, 55, 61, 62, 63, 66, 71, 77, 81, 82, 84, 88, 91, 93, 99, 101, 201, 202, 301, 303, 401, 402, 404, 501, 505, 601, 602, 603, 606, 612, 701, 707, 801, 802, 804, 808, 816, 901, 903, 909, 945, 1001, 1003, 1011, 2001, 2002, 2003
OFFSET
1,1
COMMENTS
a(n) = A084906(n) for n = 1..24.
The corresponding integers are 1, 2, 1, 3, 1, 4, 2, 1, 5, 1, 6, 3, 2, 1, 7, 1, 8, 4, 2, 1, 9, 3, 1, 11, 22, 11, 33, 11, 44, 22,...
EXAMPLE
945 is in the sequence because 9/45 + 94/5 = 19 is integer.
MAPLE
with(numtheory):U:=array(1..10):V:=array(1..10):for n from 11 to 3000 do: x:=convert(n, base, 10):n1:=nops(x):s1:=0:s2:=0:for i from 1 to n1 do:s1:=s1+x[i]*10^(i-1): U[i]:=s1:od: s2:=x[n1]:V[n1]:=s2:for j from n1-1 by -1 to 1 do:s2:=s2*10+x[j]:V[j]:=s2:od:s3:=0:ii:=0:for k from n1 by -1 to 2 while(ii=0) do:if U[k-1]=0 then ii:=1: else s3:=s3+V[k]/U[k-1]:fi:od:if s3=floor(s3) and ii=0 then printf(`%d, `, n):else fi:od:
CROSSREFS
Cf. A084906.
Sequence in context: A084854 A108237 A084906 * A232185 A118853 A117841
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Nov 20 2013
STATUS
approved