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%I A119742
%S A119742 1,112,293,18474,1026475,2207286,4088167,5970048,106081049,206969050,
%T A119742 315070851,425181862,536191973,647373084,766191895,946292976,1127404157,
%U A119742 1309292338,1497303219,1686192100,11694372101,21776190102
%N A119742 Partial sum of tetradic primes (A068188).
%C A119742 Tetradic primes are primes that are palindromes and use only the digits 
               0, 1 and 8, so they read the same backwards and upside down. a(1) 
               = 11, a(3) = 293 and a(21) = 11694372101 are primes.
%H A119742 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               TetradicNumber.html">Tetradic Number</a>.
%F A119742 a(n) = SUM[i=1..n] A068188(i). a(n) = SUM[i=1..n] {A006072(k) such that 
               A006072(k) is in A000040}.
%e A119742 a(21) = 11 + 101 + 181 + 18181 + 1008001 + 1180811 + 1880881 + 1881881 
               + 100111001 + 100888001 + 108101801 + 110111011 + 111010111 + 111181111 
               + 118818811 + 180101081 + 181111181 + 181888181 + 188010881 + 188888881 
               + 10008180001 = 11694372101.
%Y A119742 Cf. A000040, A006072, A068188.
%Y A119742 Sequence in context: A095615 A061281 A119684 this_sequence A154063 A047631 
               A008430
%Y A119742 Adjacent sequences: A119739 A119740 A119741 this_sequence A119743 A119744 
               A119745
%K A119742 base,easy,nonn,less
%O A119742 1,2
%A A119742 Jonathan Vos Post (jvospost3(AT)gmail.com), Jun 16 2006

    
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Last modified December 17 23:40 EST 2009. Contains 171025 sequences.


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