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A133971 Home primes whose homeliness is greater than 8. 12

%I #5 Apr 28 2015 14:57:42

%S 77773,178069,229751,312619,313613,313739,317741,317903,337457,337853,

%T 352489,359929,364627,374531,374587,375743,375997,378997,379103,

%U 379187,379397,379811,379997,389971,719239,733391,742283,747521,749711,771941

%N Home primes whose homeliness is greater than 8.

%C Number of terms < 10^n: 0, 0, 0, 0, 1, 31, 288, ....

%t lst = {}; f[n_] := FromDigits@ Flatten[ IntegerDigits@ Table[ #[[1]], {#[[2]]}] & /@ FactorInteger@n, 2]; h[n_] := NestWhileList[f@# &, n, !PrimeQ@# &, 1, 28]; Do[p = h[n][[ -1]]; If[ PrimeQ@p && p < 10^7 && p != n, Print[{n, p}]; AppendTo[lst, p]], {n, 2, 1000}];

%t d = 9 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Take[ Union@ lsu, 30]

%Y Cf. A037274, A118756, A133957, A133959, A133961, A133963, A133965, A133967, A133969, A133973, A133975, A133977, A133979.

%K nonn,base

%O 1,1

%A _Robert G. Wilson v_, Sep 30 2007

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Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)