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A048541 a(n) is the smallest value of m such that A002378(m), the m-th oblong number, contains exactly n 6's.

%I A048541 #22 Feb 16 2025 08:32:40
%S A048541 2,60,257,816,4082,77887,258237,816512,4546060,25820081,103276578,
%T A048541 815209584,816472087,2581876578,24834787435,258140787487,
%U A048541 1239623599592,7978512779247,78515384904912,121105886176546,816494743559742,6608227190863421,8164653370882732,81281404248860431,81649676463937177
%N A048541 a(n) is the smallest value of m such that A002378(m), the m-th oblong number, contains exactly n 6's.
%H A048541 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PronicNumber.html">Pronic Number</a>
%e A048541 From _Jesse Sealand_, Oct 07 2019: (Start)
%e A048541 a(1) = 2 since A002378(2) = 6;
%e A048541 a(2) = 60 since A002378(60) = 3660;
%e A048541 a(3) = 257 since A002378(257) = 66306;
%e A048541 a(4) = 816 since A002378(816) = 666672, etc.
%e A048541 (End).
%Y A048541 Cf. A048542, A002378.
%Y A048541 Cf. A048529, A048531, A048533, A048535, A048537, A048539, A048543, A048545, A048547.
%K A048541 nonn,base
%O A048541 1,1
%A A048541 _Patrick De Geest_, May 15 1999
%E A048541 a(14)-a(16) from _Lars Blomberg_, Jun 10 2011
%E A048541 Name edited by _Jesse Sealand_, Oct 07 2019
%E A048541 a(17) from _Giovanni Resta_, Oct 09 2019
%E A048541 a(18)-a(25) from _Max Alekseyev_, Jul 25 2024