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A133972 Home primes whose homeliness is 9. 12
178069, 229751, 313613, 313739, 317741, 317903, 337457, 337853, 352489, 374587, 375743, 375997, 379103, 379187, 379397, 379997, 389971, 719239, 733391, 742283, 1128901, 1143113, 1148593, 1392143, 1911319, 2231051, 2331997, 2333329 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Number of terms < 10^n: 0, 0, 0, 0, 0, 20, 146, ....

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 = 9 - 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, A133971, A133956, A000014, A133958, A133960, A133962, A133964, A133966, A133968, A133970, A133974, A133976, A133978.

Sequence in context: A017435 A017567 A081867 * A056748 A186062 A204787

Adjacent sequences:  A133969 A133970 A133971 * A133973 A133974 A133975

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 30 2007

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Last modified February 15 03:33 EST 2012. Contains 205694 sequences.