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 A216983 The integers sieved by 7, 5, 3, and 2. 0
 7, 1, 2, 3, 2, 5, 3, 7, 2, 3, 5, 1, 3, 1, 7, 5, 2, 1, 3, 1, 5, 7, 2, 1, 3, 5, 2, 3, 7, 1, 5, 1, 2, 3, 2, 7, 3, 1, 2, 3, 5, 1, 7, 1, 2, 5, 2, 1, 3, 7, 5, 3, 2, 1, 3, 5, 7, 3, 2, 1, 5, 1, 2, 7, 2, 5, 3, 1, 2, 3, 7, 1, 3, 1, 2, 5, 2, 7, 3, 1, 5, 3, 2, 1, 7, 5, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A number is tested for the following in order - the first test passed determines a(n): Is n mod 7 == 1? If so, write 7. Is n mod 5 == 1? If so, write 5. Is n mod 3 == 1? If so, write 3. Is n mod 2 == 1? If so, write 2. Write 1. Period 210. - Charles R Greathouse IV, Sep 22 2012 An example of an inverted sieve. Usually we would sieve 2, 3, 5, 7 which gives 2, 1, 2, 3, 2, 5, 2, 7, 2, 3, 2, 1. - Jon Perry, Sep 24 2012 LINKS EXAMPLE 4 is not 1 mod 7 or 1 mod 5 but is 1 mod 3, so a(4) = 3. MATHEMATICA Table[If[Mod[n, 7] == 1, 7, If[Mod[n, 5] == 1, 5, If[Mod[n, 3] == 1, 3, If[Mod[n, 2] == 1, 2, 1]]]], {n, 100}] (* T. D. Noe, Sep 25 2012 *) Table[Which[Mod[n, 7]==1, 7, Mod[n, 5]==1, 5, Mod[n, 3]==1, 3, Mod[n, 2]==1, 2, True, 1], {n, 90}] (* Harvey P. Dale, Mar 04 2016 *) PROG (JavaScript) for (i=1; i<90; i++) if (i%7==1) document.write("7, "); else if (i%5==1) document.write("5, "); else if (i%3==1) document.write("3, "); else if (i%2==1) document.write("2, "); else document.write("1, "); (c++) template std::string PrintSequnce_A216983(const T &max) {   std::string strSeq;   for(T i = 1; i < max; ++i)   {     if (i%7==1) strSeq+="7";     else if (i%5==1) strSeq+="5";     else if (i%3==1) strSeq+="3";     else if (i%2==1) strSeq+="2";     else strSeq+="1";     if(i

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Last modified March 22 12:23 EDT 2019. Contains 321421 sequences. (Running on oeis4.)