A321351 a(n) is the index of the row of A321350 in which n first appears, or zero if n does not appear.

0, 1, 0, 26, 3, 0, 19, 5, 0, 21, 7, 0, 23, 9, 0, 25, 11, 0, 27, 13, 0, 29, 15, 0, 2, 17, 0, 4, 19, 0, 6, 21, 0, 8, 23, 0, 10, 25, 0, 12, 27, 0, 14, 29, 0, 16, 31, 0, 18, 33, 0, 20, 35, 0, 22

Offset

1,4

Comments

No multiple of 3 appears, so a(3n) = 0 for all n.

Links

Table of n, a(n) for n=1..55.

Formula

a(n) <= (2/3)*n + 15 for n > 6.

Example

a(5) = 3, since in A321350, 2 --> (2+3)^2 --> 5, so 5 first appears in the third row.

Crossrefs

Cf. A296142, A321350.

Sequence in context: A037929 A036167 A040675 * A040663 A040664 A040665

Adjacent sequences: A321348 A321349 A321350 * A321352 A321353 A321354

Keyword

nonn,hard

Author

Jeremy F. Alm, Nov 06 2018

Status

approved