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A277830
Number of digits '0' in the set of all numbers from 0 to A014824(n) = Sum_{i=1..n} i*10^(n-i) = (0, 1, 12, 123, 1234, 12345, ...).
12
1, 1, 2, 23, 344, 4665, 58986, 713307, 8367628, 96021949, 1083676272, 12071330614, 133058985146, 1454046641578, 15775034317010, 170096022182442, 1824417011947874, 19478738020713306, 207133059219478738, 2194787382318244170, 23182441724417009624, 244170096256515775267
OFFSET
0,3
COMMENTS
The first 10 terms are given by a simple explicit formula and linear recurrence, which does not hold for n > 9. Note that A007908 (concat(1..n)) differs from A014824 (a(n) = a(n-1)*10 + n) for n > 9. - M. F. Hasler, Nov 07 2020
LINKS
FORMULA
a(n) = A083449(n) + 1 for n <= 9.
a(n) = 1 + A061217(A014824(n)), taking A061217(0)=0. - Kevin Ryde, Nov 07 2020
PROG
(PARI) print1(c=1); N=0; for(n=1, 8, print1(", "c+=sum(k=N+1, N=N*10+n, #select(d->d==0, digits(k))))) \\ For purpose of illustration.
(PARI) apply( A277830(n)={A061217(A014824(n)+!n)+1}, [0..22]) \\ Thanks to Kevin Ryde's formula. - M. F. Hasler, Nov 07 2020
KEYWORD
nonn,base,easy
AUTHOR
M. F. Hasler, Nov 01 2016
EXTENSIONS
Incorrect data, b-file, links, formulas and programs deleted by M. F. Hasler, following observations by Kevin Ryde, Nov 07 2020
STATUS
approved