A195836 Triangle read by rows which arises from A195826 in the same way as A175003 arises from A195310. Column k starts at row A000217(k).

1, 1, 1, 1, 2, 1, 3, 1, 4, 2, -1, 5, 3, -1, 7, 4, -1, 10, 5, -2, 13, 7, -3, -1, 16, 10, -4, -1, 21, 13, -5, -1, 28, 16, -7, -2, 35, 21, -10, -3, 43, 28, -13, -4, 1, 55, 35, -16, -5, 1, 70, 43, -21, -7, 1, 86, 55, -28, -10, 2, 105, 70, -35, -13, 3, 130, 86, -43, -16, 4

Offset

1,5

Comments

The sum of terms of row n is equal to the leftmost term of row n+1. It appears that this sequence is related to the generalized hexagonal numbers (A000217), A195826 and A006950 in the same way as A175003 is related to the generalized pentagonal numbers A001318, A195310 and A000041. It appears that row sums give A006950. See comments in A195825.

Links

Table of n, a(n) for n=1..70.

Example

Written as a triangle:
.  1,
.  1,
.  1,   1,
.  2,   1,
.  3,   1,
.  4,   2,  -1,
.  5,   3,  -1,
.  7,   4,  -1,
. 10,   5,  -2,
. 13,   7,  -3,   -1,
. 16,  10,  -4,   -1,
. 21,  13,  -5,   -1,
. 28,  16,  -7,   -2,
. 35,  21,  -10,  -3,
. 43,  28,  -13,  -4,   1,
. 55,  35,  -16,  -5,   1,
. 70,  43,  -21,  -7,   1,
. 86,  55,  -28, -10,   2,

Crossrefs

Cf. A000217, A006950, A175003, A195825, A195826, A195837, A195838, A195939, A195840, A195841, A195842, A195843.

Sequence in context: A266742 A120385 A216477 * A347285 A132460 A238800

Adjacent sequences: A195833 A195834 A195835 * A195837 A195838 A195839

Keyword

sign,tabf

Author

Omar E. Pol, Sep 24 2011

Status

approved