A392383 Numbers m with abundance 28: sigma(m) - 2*m = 28.

48, 2002, 5170, 29056, 133042, 114203776, 2066945668300786, 1747093491376127986, 9073730624665226838016

Offset

1,1

Comments

Contains numbers 2^(k-1)*(2^k - 29) for k in A356826.

Some large terms: 90129950220869258284697211702870016, 196660061968677859691542233869333299186, 177653158535955499078797200287396783411186, 1057046865866422509467297833709601549972088204438798336.

From Alexander Violette, May 03 2026: (Start)

2^180*3064991081731777716716694054300618367237571899483230929*100306002807464356447341699106964967409128000481349630696381582657562194582895848107106715877409 is a term.

If a larger term of the form 2^k*p*q where p and q are primes exists, then k>196. (End)

Links

Table of n, a(n) for n=1..9.

Crossrefs

Deficiency k: A191363 (k=2), A125246 (k=4), A141548 (k=6), A125247 (k=8), A101223 (k=10), A141549 (k=12), A141550 (k=14), A125248 (k=16), A223608 (k=18), A223607 (k=20), A223606 (k=22), A385255 (k=24), A275702 (k=26), A392382 (k=28), A387352 (k=32), A175730 (k=42), A101259 (k=54), A275997 (k=64), A389702 (k=90).

Abundance k: A088831 (k=2), A088832 (k=4), A087167 (k=6), A088833 (k=8), A223609 (k=10), A141545 (k=12), A141546 (k=14), A141547 (k=16), A223610 (k=18), A223611 (k=20), A223612 (k=22), A223613 (k=24), A275701 (k=26), A392383 (k=28), A175989 (k=32), A275996 (k=64), A389703 (k=90), A292626 (k=128).

Cf. A356826.

Sequence in context: A274958 A165043 A301859 * A233259 A049678 A162913

Adjacent sequences: A392380 A392381 A392382 * A392384 A392385 A392386

Keyword

nonn,more

Author

Max Alekseyev, Jan 09 2026

Status

approved