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A107613 Numbers n such that both n and prime(n) consist of square digits (0,1,4,9). 1

%I #18 Feb 07 2019 02:18:22

%S 94,1140,9109,10404,10449,41104,110000,110010,114101,910140,910190,

%T 910191,940111,940141,940409,11049914,94011001,94011004,94019941,

%U 94019990,94109190,94109191,94440910,190004449,190011049,190011090,190011091,190011909,190011999,190149101

%N Numbers n such that both n and prime(n) consist of square digits (0,1,4,9).

%C Corresponding primes are: 491, 9199, 94441, 109441, 109919, 494441, 1441049, 1441199, 1499149, which form a subsequence of A061246 (primes with square digits).

%H Chai Wah Wu, <a href="/A107613/b107613.txt">Table of n, a(n) for n = 1..216</a>

%t Do[id=Union[IntegerDigits[Prime[n]], IntegerDigits[n]];If[Count[id, 2]+Count[id, 3]+Count[id, 5]+Count[id, 6]+Count[id, 7]+Count[id, 8]==0, Print[n]], {n, 200000}]

%Y Cf. A061246.

%K nonn,base

%O 1,1

%A _Zak Seidov_, May 17 2005

%E a(10)-a(30) from _Chai Wah Wu_, Jan 30 2019

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Last modified March 29 05:48 EDT 2024. Contains 371265 sequences. (Running on oeis4.)