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A082883 Primes p(x) satisfying the following conditions: [1]# A082882(x)=1; [2]# {p(x),p(x+1)} are not twin primes; [3]# values of A075860(j) for j composites between these two non-twin primes are identical. See also A075860, A082880-A082882. 1

%I #7 Oct 15 2013 22:31:57

%S 103,457,1009,1663,2953,3079,6043,12007,17707,20749,21499,25579,28537,

%T 30703,41227,54367,55663,59443,66973,70309,81547,83557,90019,97003,

%U 101359,102559,105367,108499,116239,120847,126019,129733,133873,138403

%N Primes p(x) satisfying the following conditions: [1]# A082882(x)=1; [2]# {p(x),p(x+1)} are not twin primes; [3]# values of A075860(j) for j composites between these two non-twin primes are identical. See also A075860, A082880-A082882.

%e p[2033]=17007 is here because next prime is 17013;

%e for the five j inter-prime composites

%e i.e. if j is from {17008,..,17012} the values

%e of A075860 are identical: {7,7,7,7,7}, so A082882(2033)=1;

%e Smallest such example is a(1)=103 with this sophisticated

%e property:for i={104,105,106} the fixed points of A008472(i)

%e i.e. values of A075860(i) are uniformly equal to 2.

%t ffi[x_] := Flatten[FactorInteger[x]] lf[x_] := Length[FactorInteger[x]] ba[x_] := Table[Part[ffi[x], 2*w-1], {w, 1, lf[x]}] sopf[x_] := Apply[Plus, ba[x]] Do[s=Length[Union[tik=Table[FixedPoint[sopf, j], {j, 1+Prime[n], -1+Prime[n+1]}]]]; If[Equal[s, 1]&&!PrimeQ[2+Prime[n]], Print[Prime[n]]], {n, 1, 100000}]

%Y Cf. A008472, A075860, A082880-A082882.

%K nonn

%O 1,1

%A _Labos Elemer_, Apr 16 2003

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Last modified April 23 07:57 EDT 2024. Contains 371905 sequences. (Running on oeis4.)