A378447 Difference between {the number of distinct sums of distinct divisors of n} and {the number of distinct sums of distinct proper divisors of n}.

1, 2, 2, 4, 2, 6, 2, 8, 4, 8, 2, 12, 2, 8, 8, 16, 2, 18, 2, 20, 8, 8, 2, 24, 4, 8, 8, 28, 2, 30, 2, 32, 8, 8, 8, 36, 2, 8, 8, 40, 2, 42, 2, 32, 28, 8, 2, 48, 4, 32, 8, 32, 2, 54, 8, 56, 8, 8, 2, 60, 2, 8, 30, 64, 8, 66, 2, 32, 8, 70, 2, 72, 2, 8, 32, 32, 8, 78, 2, 80, 16, 8, 2, 84, 8, 8, 8, 88, 2, 90, 8, 32, 8, 8, 8

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

Formula

a(n) = A119347(n) - A193279(n).

Prog

(PARI) A378447(n) = (A119347(n) - A193279(n));
(PARI) A378447(n) = { my(c1=[0], c2=[0]); fordiv(n, d, c1 = Set(concat(c1, vector(#c1, i, c1[i]+d))); if(d<n, c2 = Set(concat(c2, vector(#c2, i, c2[i]+d))))); (#c1-#c2); }; \\ (see A119347 and A193279)

Crossrefs

Cf. A119347, A193279.

Sequence in context: A107067 A331580 A320389 * A046801 A348717 A316437

Adjacent sequences: A378444 A378445 A378446 * A378448 A378449 A378450

Keyword

nonn,new

Author

Antti Karttunen, Nov 29 2024

Status

approved