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Numbers k whose decimal representation, read as a base-23 value and divided by k, yields an integer.
2

%I #40 Jan 10 2024 05:04:40

%S 1,2,3,4,5,6,7,8,9,13,26,39,169,221,442,663,884,2405,2873,2912,5980,

%T 26455,28730,29120,31667,42441,48841,52900,74435,84882,104650,132808,

%U 139380,413738,20392554,23490402,25209381,32287569,234904020,239235484

%N Numbers k whose decimal representation, read as a base-23 value and divided by k, yields an integer.

%C Original name: Base 23 value of decimal denominator divided by this decimal value (n) is an integer.

%C Next term is > 2*10^14 - 1. - _Frank A. Stevenson_, Jan 02 2024

%C a(68) <= 339601420613312. - _David A. Corneth_, Jan 02 2024

%H Frank A. Stevenson, <a href="/A032577/b032577.txt">Table of n, a(n) for n = 1..67</a>

%e 2405 is a term: 2405_23 = 26455 = 2405*11. - _Jon E. Schoenfield_, Oct 25 2019

%o (Python) list(filter(lambda n: int(str(n),23) % n==0, [i for i in range(1,500000)])) # _Frank A. Stevenson_, Jan 02 2024

%o (PARI) is(n) = denominator(fromdigits(digits(n), 23)/n) == 1 \\ _David A. Corneth_, Jan 02 2024

%Y Cf. A032578, A032563.

%K nonn,base

%O 1,2

%A _Patrick De Geest_, Apr 15 1998

%E More terms from Larry Reeves (larryr(AT)acm.org), Sep 27 2000

%E Offset changed and Name edited by _Jon E. Schoenfield_, Oct 25 2019