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Number of (not necessarily proper) vertex colorings of the truncated cube using at most n colors.
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%I #29 Nov 28 2024 11:13:17

%S 1,352744,5884691769,5864100125056,1241764261950625,98716288267057896,

%T 3991275742289356969,98382635628154476544,1661800900370941653561,

%U 20833333346104183585000,205202764127643987528241,1656184316900213910466944,11308349383297867766174569

%N Number of (not necessarily proper) vertex colorings of the truncated cube using at most n colors.

%C Also the number of vertex colorings of the rhombicuboctahedron up to rotation and reflection. - _Peter Kagey_, Nov 27 2024

%H Marko R. Riedel et al., <a href="http://math.stackexchange.com/questions/1854935/">Truncated objects coloring</a>, Mathematics Stack Exchange (Jul 10 2016).

%H Marko R. Riedel, <a href="/A274900/a274900.maple.txt">Maple code for sequences A274900, A274901, A274902</a>.

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Truncated_cube">Truncated cube</a>

%F a(n) = 1/48*n^24 + 1/8*n^14 + 13/48*n^12 + 1/6*n^8 + 1/4*n^6 + 1/6*n^4 = n^4*(n^20 + 6*n^10 + 13*n^8 + 8*n^4 + 12*n^2 + 8)/48.

%e Cycle index: 1/48*s[1]^24 + 1/8*s[2]^10*s[1]^4 + 13/48*s[2]^12 + 1/6*s[3]^8 + 1/4*s[4]^6 + 1/6*s[6]^4.

%t Table[1/48 n^24 + 1/8 n^14 + 13/48 n^12 + 1/6 n^8 + 1/4 n^6 + 1/6 n^4, {n, 25}] (* _Vincenzo Librandi_, Jul 11 2016 *)

%o (Magma) [1/48*n^24+1/8*n^14+13/48*n^12+1/6*n^8+1/4*n^6+1/6*n^4: n in [1..20]]; // _Vincenzo Librandi_, Jul 11 2016

%o (PARI) a(n) = 1/48*n^24 + 1/8*n^14 + 13/48*n^12 + 1/6*n^8 + 1/4*n^6 + 1/6*n^4 \\ _Felix Fröhlich_, Jul 12 2016

%Y Cf. A274901, A274902.

%K nonn,easy

%O 1,2

%A _Marko Riedel_, Jul 10 2016