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 A102111 Iccanobirt numbers (1 of 15): a(n) = a(n-1) + a(n-2) + R(a(n-3)), where R is the digit reversal function A004086. 19
 0, 0, 1, 1, 2, 4, 7, 13, 24, 44, 99, 185, 328, 612, 1521, 2956, 4693, 8900, 20185, 33049, 53332, 144483, 291848, 459666, 1135955, 2443813, 4246722, 12285846, 19716010, 34278280, 118852511, 154192582, 281332336, 550783729, 1117407516, 2301424427 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS Digit reversal variation of tribonacci numbers A000073. Inspired by Iccanobif numbers: A001129, A014258-A014260. LINKS FORMULA A004086(a(n)) = A102119(n). MAPLE read("transforms") ; A102111 := proc(n)     option remember;     if n <= 2 then         return op(n+1, [0, 0, 1]) ;     else         return procname(n-1)+procname(n-2)+digrev(procname(n-3)) ;     end if; end proc: seq(A102111(n), n=0..20) ; # R. J. Mathar, Nov 17 2012 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]+a[n-2]+R[a[n-3]]; Table[a[n], {n, 0, 40}] PROG (Python) def R(n):   n_str = str(n)   reversedn_str = n_str[::-1]   reversedn = int(reversedn_str)   return reversedn def A102111(n):   if n == 0:     return 0   elif n == 1:     return 0   elif n == 2:     return 1   elif n >= 3:     return A(n-1)+A(n-2)+R(A(n-3)) for i in range(0, 20):   print(A102111(i)) # Dylan Delgado, Oct 23 2019 (MAGMA) a:=[0, 0, 1]; [n le 3 select a[n] else Self(n-1) + Self(n-2) + Seqint(Reverse(Intseq(Self(n-3)))):n in [1..36]]; // Marius A. Burtea, Oct 23 2019 CROSSREFS Cf. A102112-A102125. Sequence in context: A160254 A276661 A005318 * A224704 A265826 A059633 Adjacent sequences:  A102108 A102109 A102110 * A102112 A102113 A102114 KEYWORD nonn,base,easy AUTHOR Jonathan Vos Post and Ray Chandler, Dec 30 2004 STATUS approved

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Last modified December 15 04:20 EST 2019. Contains 329991 sequences. (Running on oeis4.)