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A133973 Home primes whose homeliness is greater than 9. 12
77773, 312619, 359929, 364627, 374531, 378997, 379811, 747521, 749711, 771941, 777643, 1173463, 1355021, 1389281, 1929311, 1991153, 2314723, 2315641, 2333797, 2336263, 2337397, 2337547, 2337607, 2337691, 2339929, 2373823, 2389853 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of terms < 10^n: 0, 0, 0, 0, 1, 11, 142, ....

LINKS

Table of n, a(n) for n=1..27.

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 = 10 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Take[ Union@ lsu, 30]

CROSSREFS

Cf. A037274, A118756, A133957, A133959, A133961, A133963, A133965, A133967, A133969, A133971, A133975, A133977, A133979.

Sequence in context: A235979 A087026 A133971 * A133974 A321235 A266967

Adjacent sequences:  A133970 A133971 A133972 * A133974 A133975 A133976

KEYWORD

nonn,base

AUTHOR

Robert G. Wilson v, Sep 30 2007

STATUS

approved

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Last modified May 17 14:19 EDT 2022. Contains 353746 sequences. (Running on oeis4.)