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%I #29 Jul 04 2021 01:57:07
%S 1,7,32,49,61,91,169,224,791,1568,10304,34112,160832,733376,966721,
%T 1127392,4197571,10914848,13250272,15000608,62776133,70412363,82053664
%N Numbers k that divide the (left) concatenation of all numbers <= k written in base 15 (most significant digit on left).
%C No other terms below 10^8.
%C No multiple of 3 or 5 can be in this sequence, since the numbers resulting from these concatenations are all congruent to 1 mod 15. - _Alonso del Arte_, Sep 16 2016
%H <a href="/index/N#concat">Index entries for related sequences</a>
%e In base 15, 7654321 is 84557956 in decimal, and we verify that this is a multiple of 7, as 84557956/7 = 12079708. Hence 7 is in the sequence.
%e 87654321 base 15 is 1451432956 and 1451432956/8 = 181429119.5. Hence 8 is not in the sequence.
%t Select[Range[10^3], Divisible[FromDigits[#, 15] &@ Flatten@ Reverse@ IntegerDigits[Range@ #, 15], #] &] (* _Michael De Vlieger_, Sep 16 2016 *)
%Y Cf. A029447-A029470 (in particular, A029460), A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978.
%K nonn,base,more
%O 1,2
%A _Olivier Gérard_
%E More terms from Larry Reeves (larryr(AT)acm.org), Jun 01 2001
%E Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002
%E a(14)-a(23) from _Max Alekseyev_, May 15 2011
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