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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.

A093516 Transform of the prime sequence by the Rule137 cellular automaton.

Original entry on oeis.org

1, 3, 10, 16, 22, 26, 27, 28, 34, 35, 36, 40, 46, 50, 51, 52, 56, 57, 58, 64, 65, 66, 70, 76, 77, 78, 82, 86, 87, 88, 92, 93, 94, 95, 96, 100, 106, 112, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 130, 134, 135, 136, 142, 143, 144, 145, 146, 147, 148, 154
Offset: 1

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Author

Ferenc Adorjan (fadorjan(AT)freemail.hu)

Keywords

Comments

As described in A051006, a monotonic sequence can be mapped into a fractional real. Then the binary digits of that real can be treated (transformed) by an elementary cellular automaton. Taken resulted sequence of binary digits as a fractional real, it can be mapped back into a sequence, as in A092855.

Crossrefs

Programs

  • PARI
    {ca_tr(ca,v)= /* Calculates the Cellular Automaton transform of the vector v by the rule ca */
    local(cav=vector(8),a,r=[],i,j,k,l,po,p=vector(3));
    a=binary(min(255,ca));k=matsize(a)[2];forstep(i=k,1,- 1,cav[k-i+1]=a[i]);
    j=0;l=matsize(v)[2];k=v[l];po=1;
    for(i=1,k+2,j*=2;po=isin(i,v,l,po);j=(j+max(0,sign(po)))% 8;if(cav[j+1],r=concat(r,i)));
    return(r) /* See the function "isin" at A092875 */}