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A332931
Sum of round(sqrt(d)) where d runs through the divisors of n.
6
1, 2, 3, 4, 3, 6, 4, 7, 6, 7, 4, 11, 5, 9, 9, 11, 5, 13, 5, 13, 11, 10, 6, 19, 8, 11, 11, 16, 6, 20, 7, 17, 12, 12, 12, 24, 7, 12, 13, 22, 7, 24, 8, 19, 19, 14, 8, 30, 11, 19, 14, 20, 8, 25, 13, 26, 15, 15, 9, 37, 9, 16, 22, 25, 15, 28, 9, 22, 16, 28, 9, 40
OFFSET
1,2
LINKS
MAPLE
a:= n-> add(round(sqrt(d)), d=numtheory[divisors](n)):
seq(a(n), n=1..80); # Alois P. Heinz, Mar 02 2020
MATHEMATICA
Table[DivisorSum[n, Floor[1/2+Sqrt[#]]&], {n, 80}]
PROG
(PARI) a(n) = sumdiv(n, d, round(sqrt(d))); \\ Michel Marcus, Mar 03 2020
(Python)
from math import isqrt
from sympy import divisors
def A332931(n): return sum((m:=isqrt(d))+int(d-m*(m+1)>=1) for d in divisors(n, generator=True)) # Chai Wah Wu, Aug 03 2022
CROSSREFS
Cf. A058267 (which has the "round" outside the sum), A086671, A332932, A332933, A332934, A332935.
Sequence in context: A126630 A167234 A088043 * A248376 A138796 A186970
KEYWORD
nonn
AUTHOR
Harvey P. Dale, Mar 02 2020
STATUS
approved