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%I #6 Jul 29 2015 01:05:50
%S 7,84,861,8638,86415,864192,8641969,86419746,864197523,8641975300,
%T 86419753077,864197530854,8641975308631,86419753086408,
%U 864197530864185,8641975308641962,86419753086419739,864197530864197516
%N Partial sums of repdigits of A002281.
%F a(n) = (7/81)*(10^(n+1) - 9*n - 10). - R. Piyo (nagoya314(AT)yahoo.com), Dec 10 2004
%e 7 + 77 + 777 + 7777 + 77777 = a(5) = 86415.
%t <<NumberTheory`NumberTheoryFunctions` Table[{k, Table[Apply[Plus, Table[k*(10^n-1)/9, {n, 1, m}]], {m, 1, 35}]}, {k, 1, 9}]
%t Table[8/9*Sum[10^i - 1, {i, n}], {n, 18}] (* _Robert G. Wilson v_, Nov 20 2004 *)
%Y Cf. A057932, A002275-A002283, A099669-A099675.
%K base,nonn
%O 1,1
%A _Labos Elemer_, Nov 17 2004
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