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A247797 Lexicographically earliest permutation of prime numbers, such that adjacent terms have coprime sums of digits in decimal representation.

%I A247797 #13 Jan 08 2025 10:56:49
%S A247797 2,3,5,7,11,23,13,29,17,41,31,43,19,47,37,61,53,67,59,83,71,89,73,137,
%T A247797 79,113,97,131,101,139,103,151,107,157,109,173,127,179,149,191,163,
%U A247797 193,167,197,181,199,211,223,227,229,233,241,251,263,239,269,257
%N A247797 Lexicographically earliest permutation of prime numbers, such that adjacent terms have coprime sums of digits in decimal representation.
%C A247797 A049084(a(n)) defines a permutation of the positive integers, cf. A250552.
%H A247797 Reinhard Zumkeller, <a href="/A247797/b247797.txt">Table of n, a(n) for n = 1..10000</a>
%H A247797 Christian Mauduit and Joël Rivat, <a href="https://doi.org/10.4007/annals.2010.171.1591">Sur un problème de Gelfond: la somme des chiffres des nombres premiers</a>, Annals of Mathematics, Vol. 171, No. 3, 1591-1646, 2010.
%o A247797 (Haskell)
%o A247797 import Data.List (delete)
%o A247797 a247797 n = a247797_list !! (n-1)
%o A247797 a247797_list = f 1 $ zip a000040_list a007605_list where
%o A247797    f q' vws = g vws where
%o A247797      g  ((p,q):pqs) = if gcd q q' == 1
%o A247797                          then p : f q (delete (p,q) vws) else g pqs
%Y A247797 Cf. A000040, A007953, A007605, A049084, A250552, A119449, A119450.
%K A247797 nonn,base
%O A247797 1,1
%A A247797 _Reinhard Zumkeller_, Nov 25 2014