Search: id:A121614
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%I A121614
%S A121614 27,45,54,72,78,87,126,159,162,168,186,195,207,216,234,243,249,261,267,
%T A121614 270,276,294,324,342,348,357,375,384,405,423,429,432,438,450,483,492,
%U A121614 504,519,537,540,573,591,612,618,621,627,672,678,681,687,702,708,720
%N A121614 Numbers n that have composite sum of digits and prime sum of squares 
               of digits.
%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.
%Y A121614 Sequence in context: A124940 A114446 A141229 this_sequence A046340 A046316 
               A046373
%Y A121614 Adjacent sequences: A121611 A121612 A121613 this_sequence A121615 A121616 
               A121617
%K A121614 base,nonn
%O A121614 1,1
%A A121614 Tanya Khovanova (tanyakh(AT)yahoo.com), Sep 08 2006

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