A102112 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.

0, 0, 1, 1, 2, 4, 7, 13, 24, 62, 117, 167, 940, 1818, 2034, 11155, 17275, 74420, 142846, 162568, 885229, 1893336, 2978492, 10197702, 15039830, 38797423, 52888176, 100407789, 206394037, 1246986214, 2077887605, 6411178063, 12726051979

Offset: 0

Author

Jonathan Vos Post and Ray Chandler, Dec 30 2004

Keywords

• nonn
• base
• easy

Comments

Digit reversal variation of tribonacci numbers A000073.

Inspired by Iccanobif numbers: A001129, A014258-A014260.

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A102111-A102125.

Programs

Mathematica

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}]
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 *)

Formula

A004086(a(n)) = A102120(n).