A353795 Numbers k such that k divides A353794(k), where A353794(n) = A003958(A003973(n)) * A064989(A003973(n)).

1, 4, 12, 24, 36, 44, 72, 96, 112, 132, 180, 220, 360, 384, 396, 400, 480, 560, 660, 784, 832, 864, 1044, 1056, 1188, 1200, 1344, 1920, 1980, 2088, 2352, 2376, 2496, 2800, 3168, 3600, 3920, 4320, 4736, 5220, 5280, 5376, 5824, 5940, 6800, 6912, 7056, 7200, 7488, 8400, 8800, 9504, 9900, 10000, 10440, 10800, 11484

Offset: 1

Author

Antti Karttunen, May 12 2022

Keywords

• nonn

Comments

Of 2608 initial terms, only 188 are not in A353796. The first three of these are: 400, 784, 832.

Links

• Antti Karttunen, Table of n, a(n) for n = 1..2608; all terms <= 2^32
• Index entries for sequences computed from indices in prime factorization
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000010, A003958, A003961, A003973, A064989, A353794.

Cf. also A353796.

Programs

PARI

A003958(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1]--); factorback(f); };
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); }; \\ From A003961
A064989(n) = { my(f=factor(n>>valuation(n,2))); for(i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f); };
A353794(n) = { my(s=sigma(A003961(n))); (A003958(s)*A064989(s)); };
isA353795(n) = !(A353794(n)%n);