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A276756
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Squarefree terms of A276655.
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1
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1, 21, 30, 979, 1411, 1463, 1547, 1742, 1947, 2059, 2090, 2210, 2318, 2405, 2419, 2491, 2703, 2886, 2945, 3182, 3243, 3534, 3567, 16102, 17654, 20559, 21243, 25543, 25705, 27145, 27307, 27805, 28045, 29323, 29370, 29631, 30485, 30846, 32574, 33366, 33465, 33654
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OFFSET
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1,2
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COMMENTS
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Except for the first term, products of distinct primes p_i such that Sum_{p_i} 0.p_i is an integer.
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LINKS
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FORMULA
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PROG
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(Python)
from fractions import Fraction
from sympy import factorint, primefactors
A276756_list = [1] + [n for n in range(2, 10**6) if max(factorint(n).values()) <= 1 and sum(Fraction(p, 10**len(str(p))) for p in primefactors(n)).denominator == 1]
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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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