A206421 Corresponding values of sigma(m) of numbers in A206036.

12, 18, 12, 24, 24, 31, 18, 42, 32, 24, 60, 31, 42, 56, 72, 32, 48, 54, 48, 60, 56, 90, 42, 96, 84, 72, 48, 124, 72, 98, 54, 120, 72, 120, 80, 90, 60, 168, 96, 104, 84, 144, 126, 96, 144, 72, 114, 124, 140, 96, 168, 80, 186, 126, 84, 224, 108, 132, 120, 180

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Max Alekseyev, PARI/GP Scripts for Miscellaneous Math Problems (invphi.gp).

Formula

a(n) = A000203(A206036(n)). - Amiram Eldar, Dec 15 2024

Example

a(1) = 12 because sigma(A206036(1)) = sigma(6) = 12.

Prog

(PARI) list(lim) = my(s); for(k = 1, lim, s = sigma(k); if(invsigmaNum(s) > 1, print1(s, ", "))); \\ Amiram Eldar, Dec 15 2024, using Max Alekseyev's invphi.gp

Crossrefs

Cf. A000203, A159886 (values k such that sigma(x)= k has more than one solution), A206036 (numbers m such that sigma(m) = sigma(k) has solution for distinct k).

Sequence in context: A243609 A082241 A077294 * A365219 A232391 A025491

Adjacent sequences: A206418 A206419 A206420 * A206422 A206423 A206424

Keyword

nonn

Author

Jaroslav Krizek, Feb 07 2012

Status

approved