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A283720 Main diagonal of A283675. 2
1, -1, -16, -19619, -4294403215, -298022109672568357, -10314423865939993706950978963, -256923577039780637227768848162543179896514, -6277101735175091675863380669683250419973895230549186236030 (list; graph; refs; listen; history; text; internal format)
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

Cf. A283675.

Sequence in context: A214637 A288957 A159387 * A098175 A089232 A300615

Adjacent sequences:  A283717 A283718 A283719 * A283721 A283722 A283723

KEYWORD

sign

AUTHOR

Seiichi Manyama, Mar 15 2017

STATUS

approved

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Last modified October 21 08:47 EDT 2019. Contains 328292 sequences. (Running on oeis4.)