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A133969 Home primes whose homeliness is greater than 7. 12
3761, 13367, 31397, 77773, 132953, 178069, 229751, 233743, 233911, 312619, 313613, 313739, 313829, 317741, 317903, 333857, 333923, 337397, 337457, 337487, 337661, 337853, 337907, 352489, 357727, 359929, 364627, 370451, 373753, 374159 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of terms < 10^n: 0, 0, 0, 1, 4, 64, 606, ....

LINKS

Table of n, a(n) for n=1..30.

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 = 8 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Take[ Union@ lsu, 31]

CROSSREFS

Cf. A037274, A118756, A133957, A133959, A133961, A133963, A133965, A133967, A133971, A133973, A133975, A133977, A133979.

Sequence in context: A178162 A236051 A133967 * A133970 A252564 A137790

Adjacent sequences:  A133966 A133967 A133968 * A133970 A133971 A133972

KEYWORD

nonn,base

AUTHOR

Robert G. Wilson v, Sep 30 2007

STATUS

approved

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Last modified August 11 00:25 EDT 2020. Contains 336403 sequences. (Running on oeis4.)