A354106 Numbers k for which A354102(k) = A354102(sigma(k)).

1, 24, 2475, 2520, 2728, 5347, 6683, 8184, 8307, 8568, 9108, 9306, 10106, 11484, 12974, 16041, 17892, 20049, 23265, 25265, 26199, 30318, 32256, 32435, 38922, 39618, 40918, 44010, 44576, 44872, 50976, 55224, 55720, 56516, 58817, 63720, 63952, 64890, 65689, 66528, 67356, 69860, 72072, 73409, 74448, 75795, 79101, 83160

Offset: 1

Author

Antti Karttunen, May 18 2022

Keywords

• nonn

Comments

No common terms with A006872 in range a(2) .. a(1001).

Among the 1001 initial terms, only 3119744 and 13890816 occur also in A191217.

Links

• Antti Karttunen, Table of n, a(n) for n = 1..1001
• Index entries for sequences where odd perfect numbers must occur, if they exist at all
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000010, A000203, A354102.

Cf. also A006872, A191217, A354189, A354362.

Programs

PARI

\\ Needs also the program from A267099:
A354102(n) = eulerphi(A267099(n));
isA354106(k) = (A354102(k)==A354102(sigma(k)));