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A061811
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Multiples of 3 with all even digits.
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3
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0, 6, 24, 42, 48, 60, 66, 84, 204, 222, 228, 240, 246, 264, 282, 288, 402, 408, 420, 426, 444, 462, 468, 480, 486, 600, 606, 624, 642, 648, 660, 666, 684, 804, 822, 828, 840, 846, 864, 882, 888, 2004, 2022, 2028, 2040, 2046, 2064, 2082, 2088, 2202, 2208
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OFFSET
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1,2
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COMMENTS
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The numbers b(d) of terms from 10^(d-1) to 10^d satisfy the recurrence b(d) = 6 b(d-1) - 6 b(d-2) + 5 b(d-3) with b(1)=1, b(2)=6, b(3)=33. For d >= 4, b(d) = (3*A276508(d) - 10*A276508(d-1) + 3*A276508(d-2))/7. - Robert Israel, Feb 15 2017
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LINKS
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Robert Israel, Table of n, a(n) for n = 1..10000
Index entries for 10-automatic sequences.
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EXAMPLE
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228 has all even digits and 228 = 3*76.
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MAPLE
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N:= 4: # for all terms < 10^N
E[1, 0]:= {6}:
E[1, 1]:= {4}:
E[1, 2]:= {2, 8}:
for n from 2 to N do
for j from 0 to 2 do
E[n, j]:= map(t -> (10*t, 10*t+6), E[n-1, j]) union
map(t -> (10*t+2, 10*t+8), E[n-1, j+1 mod 3]) union
map(t -> 10*t+4, E[n-1, j+2 mod 3]);
od od:
A:=sort([0, seq(op(E[i, 0]), i=1..N)]); # Robert Israel, Feb 15 2017
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PROG
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(PARI) is(n)=n%3==0 && #setintersect(Set(digits(n)), [1, 3, 5, 7, 9])==0 \\ Charles R Greathouse IV, Feb 15 2017
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CROSSREFS
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Cf. A061810, A276508.
Sequence in context: A328180 A218291 A062899 * A252066 A031101 A112423
Adjacent sequences: A061808 A061809 A061810 * A061812 A061813 A061814
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KEYWORD
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nonn,base,easy
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AUTHOR
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Amarnath Murthy, May 28 2001
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EXTENSIONS
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More terms from Larry Reeves (larryr(AT)acm.org), May 30 2001
Offset corrected by Charles R Greathouse IV, Feb 15 2017
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STATUS
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approved
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