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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A121614 Numbers that have composite sum of digits and prime sum of squares of digits.

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%I A121614 #9 Feb 13 2021 01:08:47
%S A121614 27,45,54,72,78,87,126,159,162,168,186,195,207,216,234,243,249,261,
%T A121614 267,270,276,294,324,342,348,357,375,384,405,423,429,432,438,450,483,
%U A121614 492,504,519,537,540,573,591,612,618,621,627,672,678,681,687,702,708,720
%N A121614 Numbers that have composite sum of digits and prime sum of squares of digits.
%H A121614 Vincenzo Librandi, <a href="/A121614/b121614.txt">Table of n, a(n) for n = 1..1000</a>
%e A121614 For example: the sum of digits of 27 is 9 which is composite; the sum of squares of digits of 27 is 53 which is prime.
%t A121614 sod[k_, m_] := Plus @@ (IntegerDigits[k]^m); Select[ Table[n, {n, 1000}], (! PrimeQ[sod[ #, 1]] && PrimeQ[sod[ #, 2]]) &]
%Y A121614 Cf. A091362 (Primes p such that the sum of the digits of p is not prime, but the sum of the squares of the digits of p is prime) is a prime subsequence of this sequence.
%K A121614 base,nonn
%O A121614 1,1
%A A121614 _Tanya Khovanova_, Sep 08 2006