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a(n) = a(n-1) + a(n-2) + R(a(n-3)) + R(a(n-4)) where a(1)=a(2)=a(3)=a(4)=1 and R(n) (A004086) is the reverse of n.
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%I #14 Jun 18 2021 14:46:36

%S 1,1,1,1,4,7,13,25,49,112,244,502,1051,2206,3904,7816,19243,37174,

%T 66697,144349,292510,563698,1879315,3401746,6192718,15630610,33434152,

%U 63708721,106919440,197375245,342218854,597294436,1527006682,3125687152

%N a(n) = a(n-1) + a(n-2) + R(a(n-3)) + R(a(n-4)) where a(1)=a(2)=a(3)=a(4)=1 and R(n) (A004086) is the reverse of n.

%H Harvey P. Dale, <a href="/A074864/b074864.txt">Table of n, a(n) for n = 1..1000</a>

%t RecurrenceTable[{a[1]==a[2]==a[3]==a[4]==1, a[n]==a[n-1]+a[n-2]+ IntegerReverse[ a[n-3]]+IntegerReverse[a[n-4]]},a,{n,40}] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 10 2017 *)

%Y Cf. A000288, A074860, A074861, A074865.

%K easy,base,nonn

%O 1,5

%A _Felice Russo_, Sep 11 2002

%E More terms from _Joshua Zucker_, May 08 2006

%E Definition adapted to offset by _Georg Fischer_, Jun 18 2021