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A028354 How the astronomical clock ("Orloj") in Prague strikes the hours (digits follow 12343212343... (A028356), n-th group adds to n). 5

%I

%S 1,2,3,4,32,123,43,2123,432,1234,32123,43212,34321,23432,123432,

%T 1234321,2343212,3432123,4321234,32123432,123432123,43212343,

%U 2123432123,432123432,1,2,3,4,32,123,43,2123,432,1234,32123,43212

%N How the astronomical clock ("Orloj") in Prague strikes the hours (digits follow 12343212343... (A028356), n-th group adds to n).

%C There is a single bell, which to indicate 5 o'clock, say, strikes thrice then twice.

%D Zdenek Horsky, "Prazsky Orloj" ["The Astronomical Clock of Prague", in Czech], Panorama, Prague, 1988, pp. 76-78.

%H Michal Krížek, Alena Šolcová and Lawrence Somer, <a href="http://dml.cz/dmlcz/119666">Construction of Šindel sequences</a>, Comment. Math. Univ. Carolin., 48 (2007), 373-388.

%H N. J. A. Sloane, <a href="http://neilsloane.com/doc/sg.txt">My favorite integer sequences</a>, in Sequences and their Applications (Proceedings of SETA '98).

%t s[i_] := {1, 2, 3, 4, 3, 2}[[Mod[i, 6, 1]]]; m[k_] := If[ k == 1, 0, For[m0 = 1, True, m0++, If[k(k-1)/2 == Sum[ s[i], {i, 1, m0}], Return[m0]]]]; n[k_] := For[n0 = m[k]+1, True, n0++, If[Sum[s[i], {i, m[k]+1, n0}] == k, Return[n0]]]; a[k_] := a[k] = If[k>24, a[k-24], Table[ s[i], {i, m[k]+1, n[k]}] // FromDigits]; Array[a, 36] (* _Jean-François Alcover_, Mar 13 2016 *)

%Y Cf. A028355, A028356, A068962, A118382, A118383.

%K nonn,nice,base

%O 1,2

%A _J. H. Conway_

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Last modified June 22 12:56 EDT 2021. Contains 345380 sequences. (Running on oeis4.)