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%I #12 Dec 19 2015 00:29:11
%S 0,0,1,1,2,4,7,13,24,62,117,167,940,1818,2034,11155,17275,74420,
%T 142846,162568,885229,1893336,2978492,10197702,15039830,38797423,
%U 52888176,100407789,206394037,1246986214,2077887605,6411178063,12726051979
%N Iccanobirt numbers (2 of 15): a(n) = a(n-1) + R(a(n-2)) + a(n-3), where R is the digit reversal function A004086.
%C Digit reversal variation of tribonacci numbers A000073.
%C Inspired by Iccanobif numbers: A001129, A014258-A014260.
%H Harvey P. Dale, <a href="/A102112/b102112.txt">Table of n, a(n) for n = 0..1000</a>
%F A004086(a(n)) = A102120(n).
%t R[n_]:=FromDigits[Reverse[IntegerDigits[n]]];Clear[a];a[0]=0;a[1]=0;a[2]=1;a [n_]:=a[n]=a[n-1]+R[a[n-2]]+a[n-3];Table[a[n], {n, 0, 40}]
%t nxt[{a_,b_,c_}]:={b,c,a+FromDigits[Reverse[IntegerDigits[b]]]+c}; Transpose[ NestList[nxt,{0,0,1},40]][[1]] (* _Harvey P. Dale_, Jul 29 2013 *)
%Y Cf. A102111-A102125.
%K nonn,base,easy
%O 0,5
%A _Jonathan Vos Post_ and _Ray Chandler_, Dec 30 2004