A367727 - OEIS

A367727

a(n) is the numerator of (R(n) - 1)/(n + 1), where R(n) is the digit reversal of n.

%I #12 Dec 01 2023 15:56:15

%S -1,0,1,1,3,2,5,3,7,4,0,5,20,15,8,25,60,35,80,9,1,1,21,31,41,51,61,71,

%T 81,91,2,3,2,16,6,13,62,36,82,23,3,13,23,3,43,53,63,73,83,93,4,7,24,

%U 17,4,27,64,37,84,47,5,15,25,35,9,5,65,75,85,19,6,2,26

%N a(n) is the numerator of (R(n) - 1)/(n + 1), where R(n) is the digit reversal of n.

%H Stefano Spezia, <a href="/A367727/b367727.txt">Table of n, a(n) for n = 0..10000</a>

%t a[n_]:=Numerator[(FromDigits[Reverse[IntegerDigits[n]]]-1)/(n+1)]; Array[a,73,0]

%o (PARI) a(n) = numerator((fromdigits(Vecrev(digits(n)))-1)/(n+1)); \\ _Michel Marcus_, Nov 28 2023

%Y Cf. A004086, A367593, A367728 (denominator).

%K sign,base,easy,frac,look

%O 0,5

%A _Stefano Spezia_, Nov 28 2023