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A093517
Transform of the prime sequence by the Rule225 cellular automaton.
7
1, 4, 5, 7, 10, 13, 16, 19, 22, 26, 27, 28, 31, 34, 35, 36, 40, 43, 46, 50, 51, 52, 56, 57, 58, 61, 64, 65, 66, 70, 73, 76, 77, 78, 82, 86, 87, 88, 92, 93, 94, 95, 96, 100, 103, 106, 109, 112, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 130, 134, 135, 136, 139
OFFSET
1,2
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.
PROG
(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 */}
KEYWORD
easy,nonn
AUTHOR
Ferenc Adorjan (fadorjan(AT)freemail.hu)
STATUS
approved