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A133969 Home primes whose homeliness is greater than 7. 12

%I #5 Apr 28 2015 15:01:23

%S 3761,13367,31397,77773,132953,178069,229751,233743,233911,312619,

%T 313613,313739,313829,317741,317903,333857,333923,337397,337457,

%U 337487,337661,337853,337907,352489,357727,359929,364627,370451,373753,374159

%N Home primes whose homeliness is greater than 7.

%C Number of terms < 10^n: 0, 0, 0, 1, 4, 64, 606, ....

%t 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}];

%t d = 8 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Take[ Union@ lsu, 31]

%Y Cf. A037274, A118756, A133957, A133959, A133961, A133963, A133965, A133967, A133971, A133973, A133975, A133977, A133979.

%K nonn,base

%O 1,1

%A _Robert G. Wilson v_, Sep 30 2007

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Last modified April 24 08:55 EDT 2024. Contains 371930 sequences. (Running on oeis4.)