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A130175
2n+1 appears (last digit of 2n+1) times .
1
1, 3, 3, 3, 5, 5, 5, 5, 5, 7, 7, 7, 7, 7, 7, 7, 9, 9, 9, 9, 9, 9, 9, 9, 9, 11, 13, 13, 13, 15, 15, 15, 15, 15, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 19, 19, 19, 21, 23, 23, 23, 25, 25, 25, 25, 25, 27, 27, 27, 27, 27, 27, 27, 29, 29, 29, 29, 29, 29, 29, 29, 29, 31, 33, 33
OFFSET
1,2
LINKS
FORMULA
a(n) = a(n-1) + a(n-25) - a(n-26) for n > 26. - Robert Israel, Jun 09 2023
MAPLE
seq((2*m+1)$(2*m+1 mod 10), m=0..100); # Robert Israel, Jun 09 2023
MATHEMATICA
Table[Table[n, {Mod[n, 10]}], {n, 1, 35, 2}]//Flatten (* Harvey P. Dale, Apr 24 2018 *)
CROSSREFS
Cf. A130146.
Sequence in context: A369859 A162226 A001650 * A200266 A101290 A080605
KEYWORD
nonn,base
AUTHOR
Paul Curtz, Aug 05 2007
STATUS
approved