Search: id:A036428 Results 1-1 of 1 results found. %I A036428 %S A036428 1,225,43681,8473921,1643897025,318907548961,61866420601441, %T A036428 12001766689130625,2328280871270739841,451674487259834398561, %U A036428 87622522247536602581025,16998317641534841066320321 %N A036428 Square octagonal numbers. %C A036428 Also, numbers simultaneously octagonal and centered octagonal. - Steven Schlicker (schlicks(AT)gvsu.edu), Apr 24 2007 %D A036428 S. Schlicker, Numbers Simultaneously Polygonal and Centered Polygonal, submitted. %H A036428 Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics. %F A036428 Let x(n) + y(n)*sqrt(48) = (8+sqrt(48))*(7+sqrt(48))^n, s(n) = (y(n)+1)/ 2; then a(n) = (1/2)*(2+8*(s(n)^2-s(n))) - Steven Schlicker (schlicks(AT)gvsu.edu), Apr 24 2007 %F A036428 a(n+2)=194*a(n+1)-a(n)+32 and also a(n+1)=97*a(n)+56*(3*a(n)^2+a(n))^0.5. - Richard Choulet, Sep 26 2007 %F A036428 G.f.: x(x^2+30x+1)/[(1-x)(1-194x+x^2)]. %F A036428 a(n)=-(1/6)+(7/12)*{[97-56*sqrt(3)]^n+[97+56*sqrt(3)]^n}-(1/3)*sqrt(3)*{[97-56*sqrt(3)]^n -[97+56*sqrt(3)]^n}, with n>=0 [From Paolo P. Lava (ppl(AT)spl.at), Nov 25 2008] %p A036428 CP := n -> 1+1/2*8*(n^2-n): N:=10: u:=7: v:=1: x:=8: y:=1: k_pcp:=[1]: for i from 1 to N do tempx:=x; tempy:=y; x:=tempx*u+48*tempy*v: y:=tempx*v+tempy*u: s:=(y+1)/2: k_pcp:=[op(k_pcp),CP(s)]: end do: k_pcp; - Steven Schlicker (schlicks(AT)gvsu.edu), Apr 24 2007 %Y A036428 Cf. A000567, A016754. %Y A036428 Cf. A006060, A006051, A028230, A046184. %Y A036428 Sequence in context: A151651 A051364 A061051 this_sequence A109688 A013757 A151653 %Y A036428 Adjacent sequences: A036425 A036426 A036427 this_sequence A036429 A036430 A036431 %K A036428 nonn,easy %O A036428 1,2 %A A036428 Jean-Francois Chariot (jean-francois.chariot(AT)afoc.alcatel.fr) %E A036428 More terms from Eric Weisstein (eric(AT)weisstein.com) %E A036428 Edited by N. J. A. Sloane (njas(AT)research.att.com), Oct 02 2007 Search completed in 0.001 seconds