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A133970 Home primes whose homeliness is 8. 12
3761, 13367, 31397, 132953, 233743, 233911, 313829, 333857, 333923, 337397, 337487, 337661, 337907, 357727, 370451, 373753, 374159, 375407, 375979, 379433, 379859, 383557, 397673, 397751, 397829, 399241, 409823, 473659, 616789, 733331 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of terms < 10^n: 0, 0, 0, 1, 3, 33, 318, ....

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]] && lst[[n - 1]] != lst[[n]] && lst[[n]] != lst[[n + d + 1]], AppendTo[lsu, lst[[n]]]], {n, 188004 - d - 1}]; Take[Union@ lsu, 35]

CROSSREFS

Cf. A037274, A118756, A133969, A133956, A000014, A133958, A133960, A133962, A133964, A133966, A133968, A133972, A133974, A133976, A133978.

Sequence in context: A236051 A133967 A133969 * A252564 A137790 A300796

Adjacent sequences:  A133967 A133968 A133969 * A133971 A133972 A133973

KEYWORD

nonn,base

AUTHOR

Robert G. Wilson v, Sep 30 2007

STATUS

approved

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Last modified September 23 09:03 EDT 2020. Contains 337298 sequences. (Running on oeis4.)