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A133961 Home primes whose homeliness is greater than 3. 12

%I

%S 379,773,1129,2347,2383,2389,3137,3251,3331,3359,3373,3389,3593,3719,

%T 3761,3767,3797,4397,4759,7331,7457,7523,7541,7547,7823,7853,11251,

%U 13367,13883,17137,17317,19157,19181,22367,22397,23131,23167,23173

%N Home primes whose homeliness is greater than 3.

%C Number of terms < 10^n: 0, 0, 2, 26, 221, 1843, 14516, ....

%e (42,74,237,379) -> 379, etc.

%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 = 4 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Take[ Union@ lsu, 40]

%Y Cf. A037274, A118756, A133957, A133959, A133963, A133965, A133967, A133969, A133971, A133973, A133975, A133977, A133979.

%K nonn,base

%O 1,1

%A _Robert G. Wilson v_, Sep 30 2007

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Last modified August 14 19:09 EDT 2020. Contains 336483 sequences. (Running on oeis4.)