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A117843 Primes produced by a pyramidal ( three variable sequence) that is based on the Euler totient and multiperfect sigma functions. 0

%I #4 Mar 12 2014 16:36:52

%S 2,3,5,7,11,13,17,19,29,43,173,179,193,683,1657,2731,3677,3733,4001,

%T 5743,7823,7841,7901,9421,63031,63773,93287,157229,213539,235447,

%U 1008503,1849259,3144571,16262297,4146957827,24968880823,499377616471

%N Primes produced by a pyramidal ( three variable sequence) that is based on the Euler totient and multiperfect sigma functions.

%C This function is Gaukman type of prime function in three variables.

%F phi[p_] = p*(p + gap) - p - (p + gap) + 1 sigma[p_] = gap*p*(p + gap) r0,r1 solutions to: phi[n+2]=sigma[n] f[n0_, m_, gap_] = ((r0)^n0 + (r1)^n0)/gap^m a(n) = if[PrimeQ[f[n,m,2*k]]==True.f[n,m,2*k]]

%t phi[p_] = p*(p + gap) - p - (p + gap) + 1 a = phi[n + 2] sigma[p_] = gap*p*(p + gap) b = sigma[n] c = Expand[a - b] a = Table[Table[Table[Floor[f[n, m, 2*k]], {m, 1, n}], {n, 1, 10}], {k, 1, 10}] aa = Flatten[a] pp = Union[Abs[Flatten[Table[ If[PrimeQ[aa[[n]]], aa[[n]], {}], {n, 1, Length[aa]}]]]]

%Y Cf. A001359.

%K nonn,uned

%O 1,1

%A _Roger L. Bagula_, Apr 30 2006

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