A058851 Sum of even composites up to n is palindromic.

4, 18, 58, 134, 178, 424, 598, 1344, 4254, 5998, 57630, 58740, 59998, 127404, 424414, 425344, 599998, 1273554, 4244414, 5722840, 5999998, 18886848, 42683384, 57725768, 59999998, 424650414, 578107368, 588254658, 588349340

Offset: 1

Author

Patrick De Geest, Dec 15 2000

Keywords

• nonn
• base

Comments

Sequence is 4 + 6 + 8 + 10 + 12 + 14 + ... + n.

6*10^n-2 for n >=0 are terms. - Chai Wah Wu, Feb 20 2021

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..40
• P. De Geest, Palindromic Sums

Crossrefs

Cf. A028553, A028554.

Formula

a(n) = 2*(1+A028553(1+n)). - R. J. Mathar, Sep 09 2015