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A278577
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Ramanujan function tau(p) as p runs through the prime powers: a(n) = A000594(A000961(n)).
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3
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1, -24, 252, -1472, 4830, -16744, 84480, -113643, 534612, -577738, 987136, -6905934, 10661420, 18643272, -25499225, -73279080, 128406630, -52843168, -196706304, -182213314, 308120442, -17125708, 2687348496, -1696965207, -1596055698, -5189203740, 6956478662, 2699296768, -15481826884, 9791485272
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OFFSET
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1,2
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LINKS
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PROG
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(Python)
from itertools import count, islice
from sympy import primefactors, divisor_sigma
def A278577_gen(): # generator of terms
yield 1
for n in count(2):
f = primefactors(n)
if len(f) == 1:
p, m = f[0], n+1>>1
yield (q:=n**4)*(p*n-1)//(p-1)-24*((0 if n&1 else (m*(35*m - 52*n) + 18*n**2)*(m*divisor_sigma(m))**2)+sum((i*(i*(i*(70*i - 140*n) + 90*n**2) - 20*n**3) + q)*divisor_sigma(i)*divisor_sigma(n-i) for i in range(1, m)))
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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