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, 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

Harvey P. Dale, Table of n, a(n) for n = 1..1000

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

Cf. A000288, A074860, A074861, A074865.

Sequence in context: A205538 A181565 A004119 * A074865 A072683 A304004

Adjacent sequences: A074861 A074862 A074863 * A074865 A074866 A074867

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