6,2

Arvind Ayyer (ayyer(AT)physics.rutgers.edu), Sep 11 2007, Table of n, a(n) for n = 6..76

G.F.=x^2*(-1+3*x-x^2+(5*x^4-6*x^3+11*x^2-6*x+1+4*x^6-12*x^5)^(1/2))/(2*(x^2-3*x+1)*(1-2*x)^2)

The sequence starts with n=6 because the smallest such object whose cartoon is below has a perimeter of 12. (1 denotes cell inside the Ferrers diagram)

1 1

111

Cf. A057410, A057406, A133106.

Sequence in context: A164270 A001794 A140289 this_sequence A034360 A050148 A024093

Adjacent sequences: A133104 A133105 A133106 this_sequence A133108 A133109 A133110

easy,nonn

Arvind Ayyer (ayyer(AT)physics.rutgers.edu), Sep 11 2007