This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
b[0] = b[1] = 0; b[2] = 1; b[n_] := b[n] = IntegerReverse[b[n - 1] + IntegerReverse[b[n - 2]] + b[n - 3]];
Reap[Do[If[PrimeQ[b[n]], Print[n]; Sow[n]], {n, 5000}]][[2, 1]] (* Jean-François Alcover, Dec 15 2017 *)
nxt[{a_,b_,c_}]:={b,c,IntegerReverse[c+IntegerReverse[b]+a]}; Select[ NestList[nxt,{0,0,1},200][[All,1]],PrimeQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 30 2017 *)
nxt[{a_,b_,c_}]:={b,c,IntegerReverse[c+IntegerReverse[b]+a]};Select[NestList[nxt,{0,0,1},100][[All,1]],PrimeOmega[#]==2&] (* Harvey P. Dale, Nov 17 2024 *)
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 *)
R[n_]:=FromDigits[Reverse[IntegerDigits[n]]];Clear[a];a[0]=0;a[1]=0;a[2]=1;a [n_]:=a[n]=R[a[n-1]+a[n-2]+a[n-3]];Table[a[n], {n, 0, 40}]
Transpose[NestList[{#[[2]],#[[3]],FromDigits[Reverse[IntegerDigits[Total[ #]]]]}&,{0,0,1},40]][[1]] (* Harvey P. Dale, Dec 04 2012 *)
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