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Perrin numbers which are divisible by the sum of their digits.
1

%I #12 Feb 08 2021 02:56:29

%S 2,3,5,7,10,12,90,209,486,644,1130,3480,963935,5209407,

%T 3233514234548132,1012112601190792234002,

%U 18348324030778496342550922713690,2107377545862489429119439140954710648307,842301502360957349559574408551746623721263774871322

%N Perrin numbers which are divisible by the sum of their digits.

%C a(20) has 64 digits and it is too large to include in the data section. - _Amiram Eldar_, Feb 08 2021

%H Amiram Eldar, <a href="/A117952/b117952.txt">Table of n, a(n) for n = 1..35</a>

%F a(n) = A001608(k): A007953(a(n)) | a(n) for some k. - _R. J. Mathar_, Jun 02 2006

%e 963935 is in the sequence because it is a Perrin number and it is divisible by the sum of the digits, 9+6+3+9+3+5 = 35.

%t Union @ Select[LinearRecurrence[{0, 1, 1}, {2, 3, 2}, 500], Divisible[#, Plus @@ IntegerDigits[#]] &] (* _Amiram Eldar_, Feb 08 2021 *)

%Y Intersection of A001608 and A005349.

%Y Cf. A007953.

%K base,nonn

%O 1,1

%A Luc Stevens (lms022(AT)yahoo.com), May 03 2006

%E More terms from _R. J. Mathar_, Jun 02 2006