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0, 0, 2, 2, 6, 10, 16, 20, 24, 32, 42, 50, 62, 74, 88, 96, 112, 124, 142, 158, 178, 198, 220, 240, 256, 280, 302, 326, 354, 382, 412, 436, 468, 500, 534, 558, 594, 630, 668, 704, 744, 784, 826, 866, 906, 950, 996, 1036, 1072, 1112, 1162, 1210, 1262, 1310, 1364, 1416, 1472, 1528, 1586, 1642, 1702, 1762
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,3
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COMMENTS
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a(n) = (number of pairs (i,j) in [1..n] X [1..n] with integral arithmetic mean) - (number of pairs (i,j) in [1..n] X [1..n] with integral geometric mean).
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LINKS
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PROG
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(Python)
from sympy.ntheory.primetest import is_square
def A362934(n): return ((n-1)**2>>1)-(sum(1 for x in range(1, n+1) for y in range(1, x) if is_square(x*y))<<1) # Chai Wah Wu, Aug 29 2023
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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