A083271 a(n) = n*tau(n) + 1.

2, 5, 7, 13, 11, 25, 15, 33, 28, 41, 23, 73, 27, 57, 61, 81, 35, 109, 39, 121, 85, 89, 47, 193, 76, 105, 109, 169, 59, 241, 63, 193, 133, 137, 141, 325, 75, 153, 157, 321, 83, 337, 87, 265, 271, 185, 95, 481, 148, 301, 205, 313, 107, 433, 221, 449, 229, 233, 119, 721

Offset

1,1

Links

Table of n, a(n) for n=1..60.

Formula

a(n) = A038040(n) + 1. - Torlach Rush, Feb 02 2019

Mathematica

a[x_] := x*DivisorSigma[0, x]+1; Table[a[w], {w, 1, 100}]

Prog

(PARI) a(n) = n*numdiv(n) + 1; \\ Michel Marcus, Jun 04 2025

Crossrefs

Cf. A000005, A083272, A038040.

Sequence in context: A042577 A092792 A238336 * A394036 A094285 A121218

Adjacent sequences: A083268 A083269 A083270 * A083272 A083273 A083274

Keyword

easy,nonn

Author

Labos Elemer, May 14 2003

Status

approved