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Numbers k such that the sum of cubes of digits of both k and k-2 are primes.
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%I #21 Sep 03 2024 15:10:17

%S 113,115,124,148,166,184,214,223,238,256,265,283,289,298,328,337,355,

%T 364,418,463,487,496,526,535,553,568,577,586,616,625,634,643,658,694,

%U 757,784,814,823,829,847,856,874,889,928,946,964,997,1013,1015,1024,1048,1066

%N Numbers k such that the sum of cubes of digits of both k and k-2 are primes.

%C Numbers k such that k and k-2 appear in A225534.

%H Charles U. Lonappan, <a href="http://www.ijrar.org/papers/IJRAR24C2221.pdf">Numbers k such that the Sum of Cubes of Digits of both k and k-2 are Primes</a>, IJRAR - International Journal of Research and Analytical Reviews, Volume 11, Issue 3 (2024), pp. 652-655.

%t q[n_] := PrimeQ[Plus @@ (IntegerDigits[n]^3)]; Select[Range[3, 1000], q[#-2] && q[#] &] (* _Amiram Eldar_, Jun 07 2021 *)

%Y Cf. A225534.

%K base,nonn

%O 1,1

%A _Charles U. Lonappan_, Jun 07 2021