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A133976 Home primes whose homeliness is 11. 12

%I #11 Mar 23 2021 15:41:25

%S 379811,1173463,2314723,2315641,2337607,3182561,3371237,3372371,

%T 3376991,3379997,3383777,3411901,3539857,3710627,3779873,3791453,

%U 3792179,3795581,3798737,3831523,3898513,7338269,7482569,7539743

%N Home primes whose homeliness is 11.

%C Number of terms < 10^n: 0, 0, 0, 0, 0, 1, 24, ... .

%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 = 11 - 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, 31]

%Y Cf. A037274, A118756, A133975, A133956, A133957, A133958, A133960, A133962, A133964, A133966, A133968, A133970, A133972, A133974, A133978.

%K nonn,base

%O 1,1

%A _Robert G. Wilson v_, Sep 30 2007

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Last modified April 25 11:39 EDT 2024. Contains 371969 sequences. (Running on oeis4.)