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A048533 a(n) is the smallest value of m such that A002378(m), the m-th oblong number, contains exactly n 2's.

%I A048533 #24 Feb 16 2025 08:32:40
%S A048533 1,16,141,458,1458,10593,36458,471933,471404,3496458,14930593,
%T A048533 149072541,471446966,149071198,14907133333,114989226548,471404524016,
%U A048533 1510636363333,14360440530228,47140441472504,149071332733333,1490343155861166,4712983368549333,24955404665166666,149070527690846966
%N A048533 a(n) is the smallest value of m such that A002378(m), the m-th oblong number, contains exactly n 2's.
%H A048533 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PronicNumber.html">Pronic Number</a>
%e A048533 From _Jesse Sealand_, Oct 06 2019: (Start)
%e A048533 a(1) = 1 since A002378(1) = 2;
%e A048533 a(2) = 16 since A002378(16) = 272;
%e A048533 a(3) = 141 since A002378(141) = 20022;
%e A048533 a(4) = 458 since A002378(458) = 210222, etc.
%e A048533 (End).
%Y A048533 Cf. A048534, A002378.
%Y A048533 Cf. A048529, A048531, A048535, A048537, A048539, A048541, A048543, A048545, A048547.
%K A048533 nonn,base
%O A048533 1,2
%A A048533 _Patrick De Geest_, May 15 1999
%E A048533 a(15)-a(16) from _Lars Blomberg_, Jun 10 2011
%E A048533 Name edited by _Jesse Sealand_, Oct 06 2019
%E A048533 a(17) from _Giovanni Resta_, Oct 09 2019
%E A048533 a(18)-a(25) from _Max Alekseyev_, Jul 25 2024