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A300517 a(n) is the concatenation n n times, n-1 n-1 times , ... , 22, 1. 2
1, 221, 333221, 4444333221, 555554444333221, 666666555554444333221, 7777777666666555554444333221, 888888887777777666666555554444333221, 999999999888888887777777666666555554444333221, 10101010101010101010999999999888888887777777666666555554444333221 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..31

MAPLE

a:= n-> parse(cat(seq((n-i)$(n-i), i=0..n-1))):

seq(a(n), n=1..12);  # Alois P. Heinz, Mar 07 2018

PROG

(Ruby)

def A300517(n)

  a = '1'

  [1] + (2..n).map{|i| a = (i.to_s * i + a.to_s).to_i}

end

p A300517(20)

CROSSREFS

Cf. A000461, A098129.

Sequence in context: A048902 A210135 A013548 * A083958 A083959 A078212

Adjacent sequences:  A300514 A300515 A300516 * A300518 A300519 A300520

KEYWORD

nonn,base

AUTHOR

Seiichi Manyama, Mar 07 2018

STATUS

approved

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Last modified January 21 03:58 EST 2022. Contains 350473 sequences. (Running on oeis4.)