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 A174932 a(n) = Sum_{d|n} A007955(d) * A000027(n/d) = Sum_{d|n} A007955(d) * (n/d), where A007955(m) = product of divisors of m. 1
 1, 4, 6, 16, 10, 54, 14, 96, 45, 130, 22, 1860, 26, 238, 270, 1216, 34, 6048, 38, 8300, 504, 550, 46, 335688, 175, 754, 864, 22484, 58, 811050, 62, 35200, 1188, 1258, 1330, 10095048, 74, 1558, 1638, 2576920, 82, 3113586, 86, 86372, 92070, 2254, 94, 255478416 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..1000 FORMULA a(n) = n*A322671(n). - Andrew Howroyd, Jan 05 2020 EXAMPLE For n = 4, A007955(n) = b(n): a(4) = b(1)*(4/1) + b(2)*(4/2) + b(4)*(4/4) = 1*4 + 2*2 + 8*1 = 16. PROG (PARI) a(n)={n*sumdiv(n, d, vecprod(divisors(d))/d)} \\ Andrew Howroyd, Jan 05 2020 (Magma) [&+[&*Divisors(d)*(n div d):d in Divisors(n)]:n in [1..50]]; // Marius A. Burtea, Jan 05 2020 (Python) from math import isqrt from sympy import divisor_count, divisors def A174932(n): return n*sum(isqrt(d)**(c-2) if (c:=divisor_count(d)) & 1 else d**(c//2-1) for d in divisors(n, generator=True)) # Chai Wah Wu, Jun 25 2022 CROSSREFS Cf. A007955 (product of divisors), A322671. Sequence in context: A154784 A328709 A062955 * A359103 A344223 A347263 Adjacent sequences: A174929 A174930 A174931 * A174933 A174934 A174935 KEYWORD nonn AUTHOR Jaroslav Krizek, Apr 02 2010 STATUS approved

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Last modified March 3 00:41 EST 2024. Contains 370499 sequences. (Running on oeis4.)