0,1

a(n) = 6*A014106(n)+7.

G.f.: (7+16*x+x^2)/(1-x)^3.

a(0) = 7; for n > 0, a(n) = a(n-1)+24*n+6.

a(2) = 12*2^2+18*2+7 = 91 = 6*14+7 = 6*A014106(2)+7.

a(3) = a(2)+24*3+6 = 91+72+6 = 169.

(MAGMA) [ 12*n^2+18*n+7: n in [0..40] ];

Cf. A014106 (n*(2*n+3)), A153286.

Sequence in context: A031395 A138906 A107938 this_sequence A159491 A106064 A038862

Adjacent sequences: A154102 A154103 A154104 this_sequence A154106 A154107 A154108

nonn

Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Jan 04 2009