A165495 First result not divisible by 4 when iterating k -> k+tau(k) from 2(2n-1)^2

7, 38, 71, 122, 178, 265, 415, 486, 602, 799, 927, 1230, 1321, 1486, 1810, 1951, 2214, 2474, 2830, 3194, 3386, 3738, 4206, 4639, 4874, 5358, 5838, 6222, 6534, 7101, 7482, 8145, 8570, 9010, 9722, 10922, 10922, 11434, 11882, 12571, 13274

Offset

1,1

Comments

This sequence and A165494 explore a critical aspect of the behavior of A064491.

Links

Table of n, a(n) for n=1..41.

Example

For a(2) we start at 2.3^2=18; 18+tau(18)=24; 24+tau(24)=32; 32+tau(32)=38, which is not divisible by 4, so a(2)=38.

Crossrefs

Cf. A064491, A165494, A165496

Sequence in context: A290176 A003352 A346278 * A369355 A034858 A249354

Adjacent sequences: A165492 A165493 A165494 * A165496 A165497 A165498

Keyword

easy,nonn

Author

Hugo van der Sanden, Sep 21 2009

Status

approved