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%I #10 Mar 22 2020 17:11:47
%S 2,5,9,14,19,28,29,40,45,60,51,88,65,90,105,114,91,150,103,178,161,
%T 160,127,252,181,202,215,268,165,352,187,306,289,278,331,462,229,320,
%U 357,506,259,542,275,474,537,392,303,706,413,586,495,590,345,720,571,764,565,520
%N a(n) = Sum_{d|n} phi(n/d) * prime(d).
%C Old name: A054523 * A000040.
%F A054523 as an infinite lower triangular matrix * A000040 (the primes) as a vector.
%F a(n) = Sum_{k=1..n} prime(gcd(n,k)). - _Ilya Gutkovskiy_, Mar 22 2020
%e a(4) = 14 = dot product of row 4 of A054523, (2, 1, 0, 1) and primes (2, 3, 5, 7) = (4 + 3 + 0 + 7) = 14.
%p A130029 := proc(n)
%p add( A054523(n,k)*ithprime(k),k=1..n) ;
%p end proc: # _R. J. Mathar_, Apr 04 2012
%o (PARI) a(n) = sumdiv(n, d, eulerphi(n/d)*prime(d)); \\ _Michel Marcus_, Mar 22 2020
%Y Cf. A000010, A000040, A054523, A129691, A130030.
%K nonn
%O 1,1
%A _Gary W. Adamson_, May 02 2007
%E New name and more terms from _Ilya Gutkovskiy_, Mar 22 2020
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