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a(n) = 7*n + 5.
32

%I #48 Oct 24 2022 00:06:31

%S 5,12,19,26,33,40,47,54,61,68,75,82,89,96,103,110,117,124,131,138,145,

%T 152,159,166,173,180,187,194,201,208,215,222,229,236,243,250,257,264,

%U 271,278,285,292,299,306,313,320,327,334,341,348,355,362,369,376,383

%N a(n) = 7*n + 5.

%H Vincenzo Librandi, <a href="/A017041/b017041.txt">Table of n, a(n) for n = 0..5000</a>

%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>

%H Leo Tavares, <a href="/A017041/a017041_1.jpg">Illustration: Conjoined Triangular Frames</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).

%F a(n) = 7*n + 5, n >= 0 (see the name).

%F a(n) = A125199(n+1,2) for n>0. - _Reinhard Zumkeller_, Nov 24 2006

%F G.f.: (5+2*x)/(1-x)^2 = 7*x/(1-x)^2 + 5/(1-x). - _Wolfdieter Lang_, Apr 10 2015

%F a(n) = A000326(n+2) - 3*A000217(n-1). - _Leo Tavares_, Sep 13 2022

%F E.g.f.: exp(x)*(5 + 7*x). - _Stefano Spezia_, Oct 10 2022

%t 7*Range[0,50]+5 (* _Vladimir Joseph Stephan Orlovsky_, Feb 19 2011 *)

%t LinearRecurrence[{2,-1},{5,12},70] (* _Harvey P. Dale_, Feb 08 2020 *)

%o (Magma) [7*n+5: n in [0..60]]; // _Vincenzo Librandi_, Jul 10 2011

%o (PARI) a(n)=7*n+5 \\ _Charles R Greathouse IV_, Jul 10 2016

%Y Cf. A002939, A016789, A017485, A125202, A186029.

%Y Cf. A000326, A000217.

%K nonn,easy

%O 0,1

%A _N. J. A. Sloane_