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%I #32 Jun 08 2022 14:36:56
%S 4,7,11,13,18,20,23,28,31,30,40,42,38,48,55,49,57,59,62,74,68,60,84,
%T 91,73,82,96,86,102,104,95,111,102,102,139,129,98,116,146,132,138,140,
%U 128,162,150,120,172,181,150,165,170,152,174,192,192,200,170,150,228,230
%N a(n) = sigma(n) + sigma(n+1).
%C a(n) is the area of the terrace in the level 1 of the polycube called "tower" described in A221529 where the longest side of its base is equal to n + 1, thus a(n) has a symmetric representation. - _Omar E. Pol_, Jul 22 2021
%F a(n) = A346533(n+1,n). - _Omar E. Pol_, Jul 22 2021
%t Total/@Partition[DivisorSigma[1,Range[70]],2,1] (* _Harvey P. Dale_, Feb 19 2018 *)
%o (PARI) for(i=1,60,print1(","sigma(i)+sigma(i+1)))
%Y Cf. A000203, A092405, A221529, A237593, A346533.
%K nonn
%O 1,1
%A _Jon Perry_, Mar 22 2004
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