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.
nxt[{a_, b_, c_}] := {b, c, c + IntegerReverse[b] + IntegerReverse[a]}; Flatten[Position[NestList[nxt,{0,0,1},3500][[All,1]],?PrimeQ]]-1 (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale, Sep 10 2016 *)
nxt[{a1_,a2_,a3_}]:={a2,a3,a3+FromDigits[Reverse[IntegerDigits[a1]]]+ FromDigits[Reverse[IntegerDigits[a2]]]}; Flatten[Position[Transpose[ NestList[nxt,{0,0,1},200]][[1]],?(PrimeOmega[#]==2&)]]-1 (* _Harvey P. Dale, Oct 17 2012 *)
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]+R[a[n-2]]+R[a[n-3]]];Table[a[n], {n, 0, 40}]
nxt[{a_,b_,c_}]:={b,c,IntegerReverse[c+IntegerReverse[b]+IntegerReverse[a]]}; NestList[ nxt,{0,0,1},40][[;;,1]] (* Harvey P. Dale, Mar 23 2023 *)
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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