This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A197410 #15 Aug 03 2014 14:37:24 %S A197410 1,3,4,21,6,216,8,315,52,432,12,80640,14,720,864,9765,18,176904,20, %T A197410 232848,1408,1512,24,149299200,186,2016,2080,460992,30,274827168,32, %U A197410 615195,2880,3240,3744,13333320000,38,3960,3808,680400000,42,702079488,44,1270080 %N A197410 Product of cumulative sums of divisors of n. %C A197410 When n is prime, a(n) = n + 1. %H A197410 Reinhard Zumkeller, <a href="/A197410/b197410.txt">Table of n, a(n) for n = 1..10000</a> %e A197410 a(4) = 21 because the divisors of 4 are 1, 2 and 4, their cumulative sums are 1, 3 and 7, and 1 * 3 * 7 = 21. %e A197410 a(5) = 6 because the divisors of 5 are 1 and 5, their cumulative sums are 1 and 6, and 1 * 6 = 6. %t A197410 Table[Times@@Table[Plus@@Take[Divisors[n], k], {k, DivisorSigma[0, n]}], {n, 44}] (* _Alonso del Arte_, Oct 14 2011 *) %t A197410 Table[Times@@Accumulate[Divisors[n]],{n,50}] (* _Harvey P. Dale_, Aug 15 2013 *) %o A197410 (PARI) a(n)=local(ds,sd);ds=divisors(n);prod(k=1,#ds,sd+=ds[k]) %o A197410 (Haskell) %o A197410 a197410 = product . scanl1 (+) . a027750_row %o A197410 -- _Reinhard Zumkeller_, Jan 26 2013 %Y A197410 Cf. A000203, A007955, A064945. %Y A197410 Cf. A027750. %K A197410 nonn,easy,nice %O A197410 1,2 %A A197410 _Franklin T. Adams-Watters_, Oct 14 2011