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A133963
Home primes whose homeliness is greater than 4.
12
773, 1129, 3137, 3251, 3389, 3593, 3761, 3797, 7541, 7853, 13367, 23167, 23251, 23557, 23719, 23743, 23761, 23773, 23929, 23971, 31193, 31397, 31973, 33191, 33331, 33769, 33797, 33863, 36389, 37199, 37307, 37463, 37547, 37573, 37607
OFFSET
1,1
COMMENTS
Number of terms < 10^n: 0, 0, 1, 10, 75, 758, 5994, ....
EXAMPLE
(10, 25, 55, 511, 773) -> 773, 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, 1000}];
d = 4 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Take[ Union@ lsu, 40]
KEYWORD
nonn,base
AUTHOR
Robert G. Wilson v, Sep 30 2007
STATUS
approved