%I #11 Jul 05 2018 02:02:38
%S 1,3,6,11,17,25,34,44,56,69,84,100,117,136,156,178,201,226,252,279,
%T 308,338,370,403,437,473,510,549,589,631,674,718,764,811,860,910,961,
%U 1014,1068,1124,1181,1239,1299,1360,1423,1487,1553,1620,1688
%N Place where n-th 1 occurs in A007336.
%F a(n) = 1 + Sum_{k=1..n-1} ceiling(sqrt(2)*k). - _Benoit Cloitre_, Jan 24 2009
%o (PARI) a(n)=1+sum(k=1,n-1,ceil(sqrt(2)*k)) \\ _Benoit Cloitre_, Jan 24 2009
%Y Cf. A007336.
%K nonn
%O 1,2
%A _Clark Kimberling_