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A133963 Home primes whose homeliness is greater than 4. 12

%I #5 Apr 28 2015 14:56:57

%S 773,1129,3137,3251,3389,3593,3761,3797,7541,7853,13367,23167,23251,

%T 23557,23719,23743,23761,23773,23929,23971,31193,31397,31973,33191,

%U 33331,33769,33797,33863,36389,37199,37307,37463,37547,37573,37607

%N Home primes whose homeliness is greater than 4.

%C Number of terms < 10^n: 0, 0, 1, 10, 75, 758, 5994, ....

%e (10, 25, 55, 511, 773) -> 773, 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, A133961, 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 16 04:38 EDT 2024. Contains 371696 sequences. (Running on oeis4.)