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A197917 Suppose n has prime factorization n=p1^a1*p2^a2*...*pk^ak and that D(n) is A006218, then n has all D(ai) even. 0
1, 16, 32, 64, 81, 128, 243, 256, 625, 729, 1296, 2187, 2401, 2592, 3125, 3888, 5184, 6561, 7776, 10000, 10368, 11664, 14641, 15552, 15625, 16807, 20000, 20736, 23328, 28561, 31104, 34992, 38416, 40000, 46656, 50000, 50625, 62208, 65536, 69984, 76832, 78125 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Equivalently, for all exponents e in the factorization of n, floor(sqrt(e)) is even. [Charles R Greathouse IV, Oct 20 2011]
LINKS
StackExchange, Question 73354
PROG
(PARI) is(n)=my(f=factor(n)[, 2]); for(i=1, #f, if(sqrtint(f[i])%2, return(0))); 1 \\ Charles R Greathouse IV, Oct 20 2011
CROSSREFS
Cf. A006218.
Sequence in context: A036967 A076468 A246550 * A317475 A335161 A239751
KEYWORD
nonn
AUTHOR
A. Neves, Oct 19 2011
STATUS
approved

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Last modified March 28 13:25 EDT 2024. Contains 371254 sequences. (Running on oeis4.)