A133961 Home primes whose homeliness is greater than 3.

379, 773, 1129, 2347, 2383, 2389, 3137, 3251, 3331, 3359, 3373, 3389, 3593, 3719, 3761, 3767, 3797, 4397, 4759, 7331, 7457, 7523, 7541, 7547, 7823, 7853, 11251, 13367, 13883, 17137, 17317, 19157, 19181, 22367, 22397, 23131, 23167, 23173

Offset

1,1

Comments

Number of terms < 10^n: 0, 0, 2, 26, 221, 1843, 14516, ....

Links

Table of n, a(n) for n=1..38.

Example

(42,74,237,379) -> 379, 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]

Crossrefs

Cf. A037274, A118756, A133957, A133959, A133963, A133965, A133967, A133969, A133971, A133973, A133975, A133977, A133979.

Sequence in context: A161612 A142752 A271265 * A133962 A027503 A340200

Adjacent sequences: A133958 A133959 A133960 * A133962 A133963 A133964

Keyword

nonn,base

Author

Robert G. Wilson v, Sep 30 2007

Status

approved