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A074864
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.
1
1, 1, 1, 1, 4, 7, 13, 25, 49, 112, 244, 502, 1051, 2206, 3904, 7816, 19243, 37174, 66697, 144349, 292510, 563698, 1879315, 3401746, 6192718, 15630610, 33434152, 63708721, 106919440, 197375245, 342218854, 597294436, 1527006682, 3125687152
OFFSET
1,5
LINKS
MATHEMATICA
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 *)
CROSSREFS
KEYWORD
easy,base,nonn
AUTHOR
Felice Russo, Sep 11 2002
EXTENSIONS
More terms from Joshua Zucker, May 08 2006
Definition adapted to offset by Georg Fischer, Jun 18 2021
STATUS
approved