%I #26 Sep 08 2022 08:44:52
%S 1,524289,1162785755,276040168411,19348364235069,628433226338621,
%T 12008254925383639,155514083261229015,1494966905748847961,
%U 11350851717672992089,71159090448414546291,380639089819037473139,1781400289746069037525,7438224249324360507861
%N Centered cube numbers: (n+1)^19+n^19.
%C Never prime, as a(n) = (2n + 1) * (n^18 + 9n^17 + 81n^16 + 444n^15 + 1716n^14 + 4956n^13 + 11088n^12 + 19650n^11 + 27966n^10 + 32206n^9 + 30086n^8 + 22748n^7 + 13820n^6 + 6656n^5 + 2486n^4 + 695n^3 + 137n^2 + 17n + 1). Semiprime for n in {1, 3, 8, 39, 41, 54, 111, 119, 141 ...}. [_Jonathan Vos Post_, Aug 27 2011]
%C Sums of consecutive pairs of terms of A010807. - _Wesley Ivan Hurt_, Jul 13 2014
%H Vincenzo Librandi, <a href="/A036097/b036097.txt">Table of n, a(n) for n = 0..10000</a>
%H B. K. Teo and N. J. A. Sloane, <a href="http://dx.doi.org/10.1021/ic00220a025">Magic numbers in polygonal and polyhedral clusters</a>, Inorgan. Chem. 24 (1985), 4545-4558.
%F a(n) = A010807(n+1) + A010807(n). - _Wesley Ivan Hurt_, Jul 13 2014
%e 1^19 + (1+1)^19 = 524289 = 3 * 174763, a semiprime.
%p A036097:=n->(n+1)^19+n^19: seq(A036097(n), n=0..20); # _Wesley Ivan Hurt_, Jul 13 2014
%t Total/@Partition[Range[0,20]^19,2,1] (* _Harvey P. Dale_, Mar 04 2013 *)
%t f[n_] := n^19; Array[f[#] + f[# + 1] &, 14, 0] (* _Robert G. Wilson v_, Jul 22 2014 *)
%o (Magma) [(n+1)^19+n^19: n in [0..20]]; // _Vincenzo Librandi_, Aug 28 2011
%Y Cf. A010807, A036096, A036096.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_.
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