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A175253 a(n) = characteristic function of numbers k such that A000203(m) = k has no solution for any m, where A000203(m) = sum of divisors of m. 2
0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = characteristic function of numbers from A007369(n). a(n) = 1 if A000203(m) not equal to n for any m, else 0. a(n) = 1 for such n that A054973(n) = 0. a(n) = 0 for such n that A054973(n) >= 1. a(n) + A175192(n) = A000012(n).

LINKS

Jaroslav Krizek, Table of n, a(n) for n = 1..10000

CROSSREFS

Cf. A074753, A202275, A202276, A175523, A007369, A007368, A007609.

Sequence in context: A129184 A283683 A118605 * A163584 A286655 A272170

Adjacent sequences:  A175250 A175251 A175252 * A175254 A175255 A175256

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Mar 14 2010

EXTENSIONS

More terms from Jaroslav Krizek, Dec 25 2011.

STATUS

approved

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Last modified April 18 10:44 EDT 2019. Contains 322209 sequences. (Running on oeis4.)