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A105980 Near-repdigit primes with at least two 4's as the repeated digit. 13

%I #16 Sep 11 2023 09:10:36

%S 443,449,4441,4447,44449,444443,444449,444444443,4444444447,

%T 44444444441,444444444443,44444444444444444447,

%U 44444444444444444444444447,4444444444444444444444444441,444444444444444444444444444443

%N Near-repdigit primes with at least two 4's as the repeated digit.

%H Harvey P. Dale, <a href="/A105980/b105980.txt">Table of n, a(n) for n = 1..26</a>

%e a(2)=449 is a term because all digits are equal to 4 except one.

%t Select[Flatten[Table[FromDigits[PadLeft[{n},x,4]],{x,3,30},{n,{1,3,7,9}}]],PrimeQ] (* _Harvey P. Dale_, Feb 18 2018 *)

%Y Cf. A105976, A105978, A107979, A105980, A105982, A365592, A365596, A365597, A365598.

%K base,nonn

%O 1,1

%A _Shyam Sunder Gupta_, Apr 29 2005

%E More terms from _Harvey P. Dale_, Feb 18 2018

%E Name clarified by _Robert Price_, Sep 10 2023

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Last modified May 11 15:15 EDT 2024. Contains 372409 sequences. (Running on oeis4.)