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A326129 a(n) = gcd(A326127(n), A326128(n)). 11
1, 1, 2, 1, 4, 0, 6, 1, 1, 2, 10, 1, 12, 4, 6, 1, 16, 1, 18, 1, 10, 8, 22, 6, 1, 10, 2, 21, 28, 12, 30, 1, 18, 14, 22, 1, 36, 16, 22, 10, 40, 12, 42, 1, 4, 20, 46, 1, 1, 1, 30, 3, 52, 12, 38, 2, 34, 26, 58, 3, 60, 28, 2, 1, 46, 12, 66, 1, 42, 4, 70, 1, 72, 34, 2, 3, 58, 12, 78, 1, 1, 38, 82, 7, 62, 40, 54, 2, 88, 2, 70, 1, 58, 44, 70, 30 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Question: Are there any other numbers than those in A000396 that satisfy a(n) = A326128(n) ?

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..20000

PROG

(PARI)

A326127(n) = (sigma(n)-core(n)-n);

A326128(n) = (n-core(n));

A326129(n) = gcd(A326127(n), A326128(n));

CROSSREFS

Cf. A000396, A007913, A326126, A326127, A326128.

Cf. also A009194, A325385, A325813, A325975, A326046, A326047, A326048, A326056, A326057, A326060, A326062, A326130, A326140, A326144.

Sequence in context: A158032 A282886 A282846 * A326144 A120112 A233150

Adjacent sequences:  A326126 A326127 A326128 * A326130 A326131 A326132

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jun 09 2019

STATUS

approved

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Last modified April 9 10:52 EDT 2020. Contains 333348 sequences. (Running on oeis4.)