Search: id:A033951 Results 1-1 of 1 results found. %I A033951 %S A033951 1,8,23,46,77,116,163,218,281,352,431,518,613,716,827,946,1073,1208, %T A033951 1351,1502,1661,1828,2003,2186,2377,2576,2783,2998,3221,3452,3691,3938, %U A033951 4193,4456,4727,5006,5293,5588,5891,6202,6521,6848,7183,7526,7877,8236 %N A033951 Write 1,2,... in clockwise spiral; sequence gives numbers on positive x axis. %H A033951 Index entries for sequences related to linear recurrences with constant coefficients %F A033951 a(n) = 4n^2+3n+1. %F A033951 G.f.: (1+5x+2x^2)/(1-x)^3. %F A033951 Equals A132774 * [1, 2, 3,...]; = binomial transform of [1, 7, 8, 0, 0, 0,...]. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Aug 28 2007 %F A033951 a(n)=8*n+a(n-1)-9 (with a(1)=1) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 09 2009] %e A033951 ... 16 5 6 7 22 ... %e A033951 ... 15 4 1 8 23 ... %e A033951 ... 14 3 2 9 24 ... %e A033951 For n=2, a(2)=8*2+1-9=8; n=3, a(3)=8*3+8-9=23; n=4, a(4)=8*4+23-9=46 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 09 2009] %t A033951 lst={};Do[p=4*n^2+3*n+1;AppendTo[lst, p], {n, 1, 6!}];lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Sep 01 2008] %o A033951 (PARI) a(n)=4*n^2+3*n+1 %Y A033951 Sequences from spirals: A001107, A002939, A007742, A033951, A033952, A033953, A033954, A033989, A033990, A033991, A002943, A033996, A033988. %Y A033951 A014848(2n+1)=a(n). %Y A033951 Cf. A132774. %Y A033951 a(n) = A016754(n) - n. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 17 2009] %Y A033951 Sequence in context: A164131 A114381 A139433 this_sequence A027054 A048467 A002765 %Y A033951 Adjacent sequences: A033948 A033949 A033950 this_sequence A033952 A033953 A033954 %K A033951 nonn,easy,nice,new %O A033951 0,2 %A A033951 Olivier Gorin (gorin(AT)roazhon.inra.fr) %E A033951 Extended (with formula) by Erich Friedman (erich.friedman(AT)stetson.edu). Search completed in 0.002 seconds