A049228 sigma(n)-n is a perfect square associated with A049226.

25, 49, 1156, 2809, 1369, 169, 225, 3025, 4489, 5929, 441, 5329, 25281, 10609, 37249, 10609, 27889, 24649, 1225, 22801, 80089, 37249, 85849, 34225, 187489, 1849, 208849, 157609, 76729, 2401, 82369, 267289, 64009, 130321, 3771364, 555025, 966289, 310249, 344569

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..300

Formula

a(n) = A000203(A049226(n)) - A049226(n). - Amiram Eldar, Aug 15 2019

Example

a(27) = 208849 = 457^2 is a term since sigma(A049226(27))) - A049226(27) = 208849.

Crossrefs

Cf. A000005, A000203, A049226, A049227.

Sequence in context: A322434 A056981 A132585 * A309828 A076637 A040600

Adjacent sequences: A049225 A049226 A049227 * A049229 A049230 A049231

Keyword

easy,nonn

Author

Enoch Haga

Extensions

Offset corrected and more terms added by Amiram Eldar, Aug 15 2019

Status

approved