A067115 Let N = 1357911131517192123252729... = concatenation of odd numbers. Then a(n) = sum of first n digits of N.
1, 4, 9, 16, 25, 26, 27, 28, 31, 32, 37, 38, 45, 46, 55, 57, 58, 60, 63, 65, 70, 72, 79, 81, 90, 93, 94, 97, 100, 103, 108
Offset: 1
Examples
a(6)= 1+3+5+7+9+1 = 26.
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..1000
Programs
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Mathematica
Module[{nn=20,codd},codd=Flatten[IntegerDigits/@(2Range[0,nn]+1)];Accumulate[ codd]] (* Harvey P. Dale, Jul 09 2021 *)