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A133959 Home primes whose homeliness is greater than 2. 12

%I #5 Apr 28 2015 14:56:26

%S 211,223,311,337,373,379,389,547,571,773,1123,1129,1153,1319,1931,

%T 2237,2311,2341,2347,2371,2383,2389,2557,2719,2797,2953,2971,3137,

%U 3167,3181,3191,3251,3257,3313,3329,3331,3347,3359,3373,3389,3449,3457,3461,3463

%N Home primes whose homeliness is greater than 2.

%C Number of terms < 10^n: 0, 0, 10, 91, 658, 5076, 39095, ....

%e {4, 22, 211} -> 211, 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, 10^7}];

%t d = 3 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Take[ Union@ lsu, 45]

%Y Cf. A037274, A118756, A133957, A133961, 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 April 19 15:34 EDT 2024. Contains 371794 sequences. (Running on oeis4.)