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A345143 Reflection of the concatenation of the previous two terms minus the previous term. 0
0, 1, 9, 82, 207, 70021, 11937681, 1867379174326, 623471971900739499585, 5859949370091168271294333980238096, 6908320893334921728606040790129494417723642675198936230 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..10.

FORMULA

a(n) = A004086(a(n-2)||a(n-1)) - a(n-1) for n >= 2, a(n) = n for n <= 1.

EXAMPLE

a(4) = 207 since 28(9) - 82 = 207.

MAPLE

a:= proc(n) option remember; `if`(n<2, n, (s-> parse(cat(seq(

      s[-i], i=1..length(s))))-a(n-1))(cat("", a(n-2), a(n-1))))

    end:

seq(a(n), n=0..11);  # Alois P. Heinz, Jun 11 2021

MATHEMATICA

a[0] = 0; a[1] = 1; a[n_] := a[n] = FromDigits[Join @@ (Reverse @ IntegerDigits[#] & /@ {a[n - 1], a[n - 2]})] - a[n - 1]; Array[a, 11, 0] (* Amiram Eldar, Jun 09 2021 *)

PROG

(Python)

def f(v): return int((str(v[-2])+str(v[-1]))[::-1]) - v[-1]

def aupton(nn):

    alst = [0, 1]

    for n in range(2, nn+1): alst.append(f(alst))

    return alst[:nn+1]

print(aupton(10)) # Michael S. Branicky, Jun 09 2021

CROSSREFS

Cf. A004086, A068109.

Sequence in context: A115988 A067506 A263816 * A275917 A293803 A263817

Adjacent sequences:  A345140 A345141 A345142 * A345144 A345145 A345146

KEYWORD

nonn,base

AUTHOR

George Bull, Jun 09 2021

STATUS

approved

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Last modified September 24 23:43 EDT 2022. Contains 356951 sequences. (Running on oeis4.)