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Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 25 (most significant digit on right).
142

%I #17 Mar 08 2020 21:36:47

%S 1,3,5,9,15,21,96,99,259,1317,2112,52711,72483,124069,633696,651632,

%T 2391984,4317312,8101536,8344672

%N Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 25 (most significant digit on right).

%C This sequence differs from A029518 in that all least significant zeros are removed before concatenation.

%C No more terms < 10^7. [_Lars Blomberg_, Oct 26 2011]

%H <a href="/index/N#concat">Index entries for related sequences</a>

%e See A061931 for example.

%t b = 25; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[c, IntegerDigits[IntegerReverse[#, b], b]], b], #] &] (* _Robert Price_, Mar 08 2020 *)

%Y Cf. A029447-A029470, A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978.

%K nonn,base,more

%O 1,2

%A Larry Reeves (larryr(AT)acm.org), May 24 2001

%E Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002

%E a(15)-a(20) from _Lars Blomberg_, Oct 26 2011