A351548 a(n) = A349745(n) divided by 2 if it is even, and 0 if A349745(n) is odd.

0, 60, 108, 336, 1232, 11088, 114240, 261888, 320320, 418880, 2790720, 2882880, 3769920, 6499584, 9801792, 16930368, 19171152, 35672000, 47736000, 51068160, 98654400, 110046720, 172540368, 229909120, 403504640, 487788480, 738152448, 755415680, 886792320, 1960686000, 2070484416, 2339064000, 2889432000

Offset: 1

Author

Antti Karttunen, Feb 18 2022

Keywords

• nonn

Comments

Questions: Are all nonzero terms abundant (in A005101)? Are all terms even? Could either be proved? See also comments in A351538 and in A351549.

The terms a(2) .. a(52) are all also practical (A005153) and Zumkeller (A083207). - Antti Karttunen, Dec 05 2024

Links

• Antti Karttunen, Table of n, a(n) for n = 1..52 (prepared from the b-file of A349745 computed by _Amiram Eldar_)
• Index entries for sequences computed from indices in prime factorization
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A005101, A005153, A083207, A326051 (all six known terms are present here), A329963, A349169, A349745, A351458, A351459, A351538.

Cf. also A351549.

Programs

PARI

A351548(n) = { my(u=A349745(n)); if(u%2,0,u/2); };

Formula

a(n) = 0 if A349745(n) is odd, a(n) = A349745(n)/2 otherwise.