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%I #15 Nov 27 2016 21:43:33
%S 1,2,8,12,24,36,128,288,384,864,972,1152,1944,3456,6144,6912,13122,
%T 18432,26244,31104,62208,69984,209952,279936,294912,497664,839808,
%U 884736,1679616,3538944,4478976,13436928,22674816,25165824,31850496,45349632
%N Numbers n such that first digit of n divides n, last digit of n divides n, number of divisors of n divides n and phi(n) divides n, where phi(n) is the Euler totient function.
%C Numbers n such that A000030(n)|n, A010879(n)|n, A000005(n)|n and A000010(n)|n.
%C Intersection of A007694, A034709, A033950 and A034837.
%H Robert G. Wilson v, <a href="/A277804/b277804.txt">Table of n, a(n) for n = 1..43</a>
%H <a href="/index/Di#divseq">Index to divisibility sequences</a>
%e a(5) = 24 because 24/2 = 12, 24/4 = 6, 24 has 8 divisors {1,2,3,4,6,8,12,24}, 24/8 = 3, phi(24) = 8 {1,5,7,11,13,17,19,23} and 24/8 = 3 (all are an integers).
%t Select[Range[50000000], Divisible[#1, First[IntegerDigits[#1]]] && Divisible[#1, Last[IntegerDigits[#1]]] && Divisible[#1, DivisorSigma[0, #1]] && Divisible[#1, EulerPhi[#1]] & ]
%Y Cf. A000005, A000010, A000030, A007694, A034709, A033950, A034837, A010879.
%K nonn,base
%O 1,2
%A _Ilya Gutkovskiy_, Nov 01 2016
%E a(24) - a(36) added by _G. C. Greubel_, Nov 02 2016
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