%I A034721
%S A034721 1,2,17,66,169,346,617,1002,1521,2194,3041,4082,5337,6826,8569,10586,
%T A034721 12897,15522,18481,21794,25481,29562,34057,38986,44369,50226,56577,
%U A034721 63442,70841,78794,87321,96442,106177,116546,127569,139266,151657
%N A034721 ( 10*n*n*n -9*n*n +2*n )/3 +1.
%Y A034721 a(n)= A034720(n) +1, where +1 counts the empty string.
%Y A034721 Sequence in context: A002430 A160469 A037420 this_sequence A107815 A042803 
               A056074
%Y A034721 Adjacent sequences: A034718 A034719 A034720 this_sequence A034722 A034723 
               A034724
%K A034721 nonn,easy
%O A034721 0,2
%A A034721 Felice Russo (felice.russo(AT)katamail.com)
%E A034721 Edited by frank.ellermann(AT)t-online.de, Mar 13 2002