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%I #21 Nov 06 2017 04:33:41
%S 0,2,2,2,2,2,1,4,0,1,2,4,4,4,4,4,3,6,2,3,2,4,4,4,4,4,3,6,2,3,2,4,4,4,
%T 4,4,3,6,2,3,2,4,4,4,4,4,3,6,2,3,2,4,4,4,4,4,3,6,2,3,1,3,3,3,3,3,2,5,
%U 1,2,4,6,6,6,6,6,5,8,4,5,0
%N Write digits for n, count endpoints (version 3).
%C Number of endpoints: 0,8 - zero, 6,9 - one, 1,2,3,4,5 - two, 7 - four. - _Michael B. Porter_, Oct 28 2017
%F a(10*n + d) = a(n) + e where e is the number of endpoints of single digit d. - _David A. Corneth_, Oct 28 2017
%e The digit 1 has two endpoints, and the digit 8 has no endpoints, so a(18) = 2. - _Michael B. Porter_, Oct 28 2017
%o (PARI) a(n)=vecsum(apply(d->[0, 2, 2, 2, 2, 2, 1, 4, 0, 1][d+1], digits(n))); \\ based on program for A027386 by _Andrew Howroyd_, _Michael B. Porter_, Oct 28 2017
%Y Cf. A027386, A027387, A027389, A055642, A100910, A102683, A268643.
%K nonn,base
%O 0,2
%A _N. J. A. Sloane_
%E a(6) corrected by _Michael B. Porter_, Oct 28 2017 (per _Andrew Howroyd_)
%E a(27) to a(80) by _Michael B. Porter_, Oct 28 2017
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