cp's OEIS Frontend

A074860 a(n) = a(n-1) + R(a(n-2)) + R(a(n-3)) where a(0)=a(1)=a(2)=1 and R(k) = A004086(k) is the reverse of k.

%I A074860 #9 Jun 17 2021 08:19:53
%S A074860 1,1,1,3,5,9,17,31,111,195,319,1021,2525,4639,11092,25708,64083,
%T A074860 173846,292644,979061,2073724,2680995,7115676,17380240,30136219,
%U A074860 41109707,136581181,298634398,550610143,1625232666,2859685613,9863026929,19691221772,32153295043
%N A074860 a(n) = a(n-1) + R(a(n-2)) + R(a(n-3)) where a(0)=a(1)=a(2)=1 and R(k) = A004086(k) is the reverse of k.
%p A074860 R:= n-> (s-> parse(cat(s[-i]$i=1..length(s))))(""||n):
%p A074860 a:= proc(n) option remember; `if`(n<3, 1,
%p A074860       a(n-1) + R(a(n-2)) + R(a(n-3)))
%p A074860     end:
%p A074860 seq(a(n), n=0..33);  # _Alois P. Heinz_, Jun 17 2021
%Y A074860 Cf. A000213, A004086.
%K A074860 easy,base,nonn
%O A074860 0,4
%A A074860 _Felice Russo_, Sep 11 2002
%E A074860 Corrected and extended by _David Garber_, Oct 23 2002
%E A074860 Offset corrected by and more terms from _Alois P. Heinz_, Jun 17 2021