OFFSET
0,3
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..26
MATHEMATICA
Table[SeriesCoefficient[Product[(1 - x^k)^(k^(n*k)), {k, 1, 10}], {x, 0, n}], {n, 0, 10}] (* Indranil Ghosh, Mar 17 2017 *)
PROG
(Ruby)
def s(k, i)
s = 0
(1..i).each{|j| s += j ** (k * j + 1) if i % j == 0}
s
end
def A(k, n)
ary = [1]
s_ary = [0] + (1..n).map{|i| s(k, i)}
(1..n).each{|i| ary << (1..i).inject(0){|s, j| s - ary[-j] * s_ary[j]} / i}
ary
end
def A283720(n)
(0..n).map{|i| A(i, i)[-1]}
end
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Mar 15 2017
STATUS
approved