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A133959
Home primes whose homeliness is greater than 2.
12
211, 223, 311, 337, 373, 379, 389, 547, 571, 773, 1123, 1129, 1153, 1319, 1931, 2237, 2311, 2341, 2347, 2371, 2383, 2389, 2557, 2719, 2797, 2953, 2971, 3137, 3167, 3181, 3191, 3251, 3257, 3313, 3329, 3331, 3347, 3359, 3373, 3389, 3449, 3457, 3461, 3463
OFFSET
1,1
COMMENTS
Number of terms < 10^n: 0, 0, 10, 91, 658, 5076, 39095, ....
EXAMPLE
{4, 22, 211} -> 211, etc.
MATHEMATICA
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}];
d = 3 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Take[ Union@ lsu, 45]
KEYWORD
nonn,base
AUTHOR
Robert G. Wilson v, Sep 30 2007
STATUS
approved