This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A060352 #36 Dec 31 2024 22:31:31 %S A060352 2,17,80,323,1214,4373,15308,52487,177146,590489,1948616,6377291, %T A060352 20726198,66961565,215233604,688747535,2195382770,6973568801, %U A060352 22082967872,69735688019,219667417262,690383311397,2165293113020,6778308875543,21182215236074,66088511536553,205891132094648 %N A060352 a(n) = n*3^n - 1. %H A060352 Harry J. Smith, <a href="/A060352/b060352.txt">Table of n, a(n) for n = 1..200</a> %H A060352 Paul Leyland, <a href="http://www.leyland.vispa.com/numth/factorization/cullen_woodall/cw.htm">Factors of Cullen and Woodall numbers</a> %H A060352 Paul Leyland, <a href="http://www.leyland.vispa.com/numth/factorization/cullen_woodall/gcw.htm">Generalized Cullen and Woodall numbers</a> %H A060352 Amelia Carolina Sparavigna, <a href="https://doi.org/10.5281/zenodo.3471358">The groupoids of Mersenne, Fermat, Cullen, Woodall and other Numbers and their representations by means of integer sequences</a>, Politecnico di Torino, Italy (2019), [math.NT]. %H A060352 Amelia Carolina Sparavigna, <a href="https://doi.org/10.18483/ijSci.2188">Some Groupoids and their Representations by Means of Integer Sequences</a>, International Journal of Sciences (2019) Vol. 8, No. 10. %H A060352 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (7,-15,9). %F A060352 G.f.: x*(2-3*x)*(1+3*x)/((1-x)*(1-3*x)^2). - _Colin Barker_, Apr 22 2012 %F A060352 a(n) = 7*a(n-1) - 15*a(n-2) + 9*a(n-3), a(1)=2, a(2)=17, a(3)=80. - _Harvey P. Dale_, Dec 14 2012 %F A060352 E.g.f.: 1 + exp(x)*(3*exp(2*x)*x - 1). - _Stefano Spezia_, Jan 05 2020 %t A060352 Table[n*3^n-1,{n,50}] (* _Vladimir Joseph Stephan Orlovsky_, May 19 2011 *) %t A060352 LinearRecurrence[{7,-15,9},{2,17,80},50] (* _Harvey P. Dale_, Dec 14 2012 *) %o A060352 (PARI) a(n) = { n*3^n - 1 } \\ _Harry J. Smith_, Jul 04 2009 %Y A060352 Cf. A060353. %K A060352 nonn,easy %O A060352 1,1 %A A060352 _Jason Earls_, Mar 31 2001