A387709 Primitive nondeficient numbers (A006039) that satisfy Euler's criteria for odd perfect numbers (A228058).

2205, 1102725, 1380825, 1442925, 1660725, 29972025, 31016925, 31065525, 38975625, 74188125, 76910625, 219983445, 712742877, 1114813125, 1594738125, 1632259629, 1653260625, 1740475737, 1776547773, 2065124061, 2101196097, 2173340169, 2317628313, 2425844421, 2497988493, 2534060529, 2642276637, 2822636817, 2858708853

Offset

1,1

Links

Table of n, a(n) for n=1..29.

Index entries for sequences where odd perfect numbers must occur, if they exist at all

Prog

(PARI)
is_A228058(n) = if(!(n%2)||(omega(n)<2), 0, my(f=factor(n), y=0); for(i=1, #f~, if(1==(f[i, 2]%4), if((1==y)||(1!=(f[i, 1]%4)), return(0), y=1), if(f[i, 2]%2, return(0)))); (y));
A341619(n) = if(sigma(n)<(2*n), 0, fordiv(n, d, if((d<n)&&(sigma(d) >= 2*d), return(0))); (1));
is_A387709(n) = (A341619(n) && is_A228058(n));

Crossrefs

Intersection of A006039 and A228058.

Subsequence of A386427.

Sequence in context: A348743 A252397 A252392 * A175915 A098192 A004931

Adjacent sequences: A387706 A387707 A387708 * A387710 A387711 A387712

Keyword

nonn

Author

Antti Karttunen, Sep 11 2025

Status

approved