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%I #21 Jul 25 2024 13:59:13
%S 9,31,890,2234,14131,30331,173031,969520,9958890,31617890,360542549,
%T 547631234,3316547890,17318486343,114017542334,356363452109,
%U 3065925634968,9995498986343,44045425415132,173193446755643,1414213562370264,4471015432706534,31575306806579083,171463720944111031,141138230008594765
%N a(n) is the smallest value of m such that A002378(m), the m-th oblong number, contains exactly n 9's.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PronicNumber.html">Pronic Number</a>
%e From _Jesse Sealand_, Oct 07 2019: (Start)
%e a(1) = 9 since A002378(9) = 90;
%e a(2) = 31 since A002378(31) = 992;
%e a(3) = 890 since A002378(890) = 792990;
%e a(4) = 2234 since A002378(2234) = 4992990, etc.
%e (End).
%Y Cf. A048548, A002378.
%Y Cf. A048529, A048531, A048533, A048535, A048537, A048539, A048541, A048543, A048545.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, May 15 1999
%E a(13)-a(16) from _Lars Blomberg_, Jun 10 2011
%E Name edited by _Jesse Sealand_, Oct 07 2019
%E a(17) from _Giovanni Resta_, Oct 09 2019
%E a(18)-a(25) from _Max Alekseyev_, Jul 25 2024