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 A004155 Sum of digits of n-th odd number. 1
 1, 3, 5, 7, 9, 2, 4, 6, 8, 10, 3, 5, 7, 9, 11, 4, 6, 8, 10, 12, 5, 7, 9, 11, 13, 6, 8, 10, 12, 14, 7, 9, 11, 13, 15, 8, 10, 12, 14, 16, 9, 11, 13, 15, 17, 10, 12, 14, 16, 18, 2, 4, 6, 8, 10, 3, 5, 7, 9, 11, 4, 6, 8, 10, 12, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS G. C. Greubel, Table of n, a(n) for n = 0..10000 FORMULA a(n) = 2n - 1 - 9*Sum_{k=1..1+floor(log_10(2n-1))} floor( (n-1)/(5*10^(k-1)) ). - Anthony Browne, Jun 18 2016 a(n) = A004092(n+5). - G. C. Greubel, Jun 19 2016 MATHEMATICA Table[Sum[DigitCount[2*n + 1][[i]]*i, {i, 9}], {n, 0, 100}] (* G. C. Greubel, Jun 19 2016 *) PROG (PARI) a(n)=sumdigits(2*n+1) \\ Charles R Greathouse IV, Jun 19 2016 CROSSREFS Cf. A004092. Sequence in context: A225985 A032764 A131669 * A163125 A167047 A065271 Adjacent sequences:  A004152 A004153 A004154 * A004156 A004157 A004158 KEYWORD nonn,base,easy AUTHOR STATUS approved

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Last modified August 4 09:03 EDT 2020. Contains 336201 sequences. (Running on oeis4.)