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%I #11 Dec 01 2023 15:56:26
%S 1,1,3,2,5,3,7,4,9,5,1,6,13,7,3,8,17,9,19,2,21,2,23,24,25,26,27,28,29,
%T 30,31,8,3,17,5,9,37,19,39,10,41,42,43,4,45,46,47,48,49,50,51,26,53,
%U 27,5,28,57,29,59,30,61,62,63,64,13,6,67,68,69,14,71,9
%N a(n) is the denominator of (R(n) - 1)/(n + 1), where R(n) is the digit reversal of n.
%H Stefano Spezia, <a href="/A367728/b367728.txt">Table of n, a(n) for n = 0..10000</a>
%t a[n_]:=Denominator[(FromDigits[Reverse[IntegerDigits[n]]]-1)/(n+1)]; Array[a,72,0]
%o (PARI) a(n) = denominator((fromdigits(Vecrev(digits(n)))-1)/(n+1)); \\ _Michel Marcus_, Nov 28 2023
%Y Cf. A004086, A367593, A367727 (numerator).
%K nonn,base,easy,frac,look
%O 0,3
%A _Stefano Spezia_, Nov 28 2023