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Numbers that can be written as the sum of two Moran numbers (see A001101).
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%I #9 Sep 08 2022 08:46:25

%S 36,39,42,45,48,54,60,63,66,69,72,81,84,87,90,102,105,108,111,126,129,

%T 132,135,138,141,144,147,151,153,154,156,159,160,162,168,170,171,173,

%U 174,175,177,178,179,180,183,189,192,194,195,196,197,198,201,208,211

%N Numbers that can be written as the sum of two Moran numbers (see A001101).

%e 36 = 18 + 18 = A001101(1) + A001101(1), so 36 is a term.

%e 39 = 18 + 21 = A001101(1) + A001101(2), so 39 is a term.

%e 87 = 42 + 45 = A001101(4) + A001101(5), so 87 is a term.

%t m = 211; morans = Select[Range[m], PrimeQ[#/Plus @@ IntegerDigits[#]] &]; Select[Range[m], Length[IntegerPartitions[#, {2}, morans]] > 0 &] (* _Amiram Eldar_, Oct 21 2020 *)

%o (Magma) moran:=func<n|n mod &+Intseq(n) eq 0 and IsPrime( n div &+Intseq(n))>; [n:n in [1..220] | #RestrictedPartitions(n,2,{k:k in [1..n-1] | moran(k)}) ne 0];

%Y Cf. A001101, A005349, A337853.

%K nonn,base

%O 1,1

%A _Marius A. Burtea_, Oct 21 2020