

A083813


a(n) = 3*(10^n1).


3



27, 297, 2997, 29997, 299997, 2999997, 29999997, 299999997, 2999999997, 29999999997, 299999999997, 2999999999997, 29999999999997, 299999999999997
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OFFSET

1,1


COMMENTS

Original definition: 3n+1 is the digit reversal of n+1.
1. a(n) = 27 + 270 + 2700 + ... up to n terms = sum of n terms of the geometric progression with the first term 27 and common ratio 10.
2. a(n) = 27*A000042(n) (the unary sequence).
Equals A086574 restricted to positive indices. See that entry for many more comments, formulas and references.  M. F. Hasler, Jul 29 2016


LINKS



MATHEMATICA

3(10^Range[20]1) (* or *) Table[10 FromDigits[PadRight[{2}, n, 9]]+7, {n, 20}] (* Harvey P. Dale, Jan 25 2020 *)


CROSSREFS

Essentially a duplicate of A086574.


KEYWORD

nonn


AUTHOR

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 08 2003


EXTENSIONS



STATUS

approved



