A160944 - OEIS

A160944

a(n)= n * digital sum(n-1) * digital sum(n+1)

0, 6, 24, 60, 120, 210, 336, 504, 72, 180, 33, 96, 195, 336, 525, 768, 1071, 1440, 342, 600, 168, 330, 552, 840, 1200, 1638, 2160, 2772, 870, 1320, 465, 768, 1155, 1632, 2205, 2880, 3663, 4560, 1716, 2400, 984, 1470, 2064, 2772, 3600, 4554, 5640, 6864

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..48.

FORMULA

a(n)=n*A007953(n-1)*A007953(n+1).

EXAMPLE

a(8)=8*ds(7)*ds(9)=8*7*9=504.

a(15)=15*ds(14)*ds(16)=15*5*7=525.

a(26)=26*ds(25)*ds(27)=26*7*9.

MATHEMATICA