%I A161713
%S A161713 1,2,4,7,14,28,49,71,79,46,70,329,812,1624,2897,4793,7507,11270,
%T A161713 16352,23065,31766,42860,56803,74105,95333,121114,152138,
%U A161713 189161,233008,284576,344837,414841,495719,588686,695044
%V A161713 1,2,4,7,14,28,49,71,79,46,-70,-329,-812,-1624,-2897,-4793,-7507,-11270,
%W A161713 -16352,-23065,-31766,-42860,-56803,-74105,-95333,-121114,-152138,
%X A161713 -189161,-233008,-284576,-344837,-414841,-495719,-588686,-695044
%N A161713 (-n^5 + 15*n^4 - 65*n^3 + 125*n^2 - 34*n + 40)/40.
%C A161713 {a(k): 0 <= k < 6} = divisors of 28:
%C A161713 a(n) = A027750(A006218(27) + k + 1), 0 <= k < A000005(28).
%H A161713 R. Zumkeller, <a href="a161700.txt">Enumerations of Divisors</a>
%F A161713 a(n) = C(n,0) + C(n,1) + C(n,2) + 3*C(n,4) - 3*C(n,5).
%F A161713 G.f.: -(-1+4*x-7*x^2+7*x^3-7*x^4+7*x^5)/(-1+x)^6. [From R. J. Mathar 
               (mathar(AT)strw.leidenuniv.nl), Jun 18 2009]
%e A161713 Differences of divisors of 28 to compute the coefficients of their interpolating 
               polynomial, see formula:
%e A161713 1 ... 2 ... 4 ... 7 ... 14 ... 28
%e A161713 .. 1 ... 2 ... 3 ... 7 ... 14
%e A161713 ..... 1 ... 1 ... 4 ... 7
%e A161713 ........ 0 ... 3 ... 3
%e A161713 ........... 3 ... 0
%e A161713 ............. -3.
%Y A161713 A005408, A000124, A016813, A086514, A000125, A058331, A002522, A161701, 
               A161702, A161703, A000127, A161704, A161706, A161707, A161708, A161710, 
               A080856, A161711, A161712, A161715, A006261.
%Y A161713 A018254, A161700, A161856. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), 
               Jun 21 2009]
%Y A161713 Sequence in context: A018254 A018660 A018692 this_sequence A018330 A068060 
               A057744
%Y A161713 Adjacent sequences: A161710 A161711 A161712 this_sequence A161714 A161715 
               A161716
%K A161713 sign
%O A161713 0,2
%A A161713 Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jun 17 2009