A133964 Home primes whose homeliness is 5.
773, 1129, 3137, 3251, 3593, 3797, 7541, 7853, 23167, 23557, 23719, 23743, 23773, 23971, 31973, 33191, 33331, 33769, 33863, 37307, 37573, 37691, 37997, 39733, 39929, 47797, 53101, 61613, 67349, 67709, 71129, 71171, 71443, 71719, 73181
Offset: 1
Examples
Only (10, 25, 55, 511, 773) -> 773, etc.
Crossrefs
Programs
-
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 = 5 - 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, 45]
Comments