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Transform of the prime sequence by the Rule137 cellular automaton.
7

%I #3 Jun 29 2008 03:00:00

%S 1,3,10,16,22,26,27,28,34,35,36,40,46,50,51,52,56,57,58,64,65,66,70,

%T 76,77,78,82,86,87,88,92,93,94,95,96,100,106,112,116,117,118,119,120,

%U 121,122,123,124,125,126,130,134,135,136,142,143,144,145,146,147,148,154

%N Transform of the prime sequence by the Rule137 cellular automaton.

%C 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.

%H Ferenc Adorjan, <a href="http://web.axelero.hu/fadorjan/aronsf.pdf">Binary mapping of monotonic sequences - the Aronson and the CA functions</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ElementaryCellularAutomaton.html">Elementary Cellular Automaton</a>

%o (PARI) {ca_tr(ca,v)= /* Calculates the Cellular Automaton transform of the vector v by the rule ca */

%o local(cav=vector(8),a,r=[],i,j,k,l,po,p=vector(3));

%o a=binary(min(255,ca));k=matsize(a)[2];forstep(i=k,1,- 1,cav[k-i+1]=a[i]);

%o j=0;l=matsize(v)[2];k=v[l];po=1;

%o 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)));

%o return(r) /* See the function "isin" at A092875 */}

%Y Cf. A092855, A051006, A093510, A093511, A093512, A093513, A093514, A093515, A093517.

%K easy,nonn

%O 1,2

%A Ferenc Adorjan (fadorjan(AT)freemail.hu)