%I A062885
%S A062885 0,2,2,6,4,20,6,42,8,864,20,42086,420,208,42,420,64,8642086,864,642086,
20,42,42086,
%T A062885 6420864,864,1,208,864,420,8642,420,86420864208642,64,420864208642086,
8642086,420,864,
%U A062885 86420864208642,642086,86420864208642086420864208642,1,642086420864208642,
42,86,2086420864,6420864208642086420,6420864,2086420864208642086,
864,208642,1,864208642086420864208642086420864
%V A062885 0,2,2,6,4,20,6,42,8,864,20,42086,420,208,42,420,64,8642086,864,642086,
20,42,42086,
%W A062885 6420864,864,-1,208,864,420,8642,420,86420864208642,64,420864208642086,
8642086,420,864,
%X A062885 86420864208642,642086,86420864208642086420864208642,-1,642086420864208642,
42,86,2086420864,6420864208642086420,6420864,2086420864208642086,
864,208642,-1,864208642086420864208642086420864
%N A062885 Smallest multiple of n with property that digits are even and each digit
is two less (mod 10) than the previous digit, if such a multiple
exists; otherwise -1.
%H A062885 <a href="Sindx_Fi.html#final">Index entries for sequences related to
final digits of numbers</a>
%H A062885 Don Reble, <a href="a062885.txt">Analysis of this sequence</a>
%e A062885 a(7) = 42 = 7*6 has decreasing even digits.
%e A062885 For n = 25, the conditions require that the desired multiple 25k have
k even, i.e. 25k = 25(2i) = 50i = (5i)(10). Thus the final digit
is 0, so the next-to-last digit must be 2, but this is impossible
since 5i always ends in 0 or 5. Thus a(25) = -1. - John W. Layman
(layman(AT)math.vt.edu), Nov 01 2001
%Y A062885 Cf. A062884.
%Y A062885 Sequence in context: A067045 A083467 A061807 this_sequence A062293 A054516
A062400
%Y A062885 Adjacent sequences: A062882 A062883 A062884 this_sequence A062886 A062887
A062888
%K A062885 base,easy,nice,sign
%O A062885 0,2
%A A062885 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jun 28 2001
%E A062885 More terms and better description from John W. Layman (layman(AT)math.vt.edu),
Nov 01 2001
%E A062885 Further terms from Jud McCranie, Nov 01, 2001
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