A195840 - OEIS

A195840

Triangle read by rows which arises from A195830, in the same way as A175003 arises from A195310. Column k starts at row A074377(k).

%I #13 Mar 30 2012 17:34:09

%S 1,1,1,1,1,1,1,1,2,1,3,1,4,1,-1,4,1,-1,4,1,-1,4,1,-1,4,2,-1,5,3,-1,7,

%T 4,-1,10,4,-2,12,4,-3,13,4,-4,13,4,-4,13,5,-4,14,7,-4,-1,16,10,-4,-1,

%U 21,12,-5,-1,27,13,-7,-1,32,13,-10,-1,34

%N Triangle read by rows which arises from A195830, in the same way as A175003 arises from A195310. Column k starts at row A074377(k).

%C The sum of terms of row n is equal to the leftmost term of row n+1. This sequence is related to the generalized decagonal numbers A074377, A195830 and A195850 in the same way as A175003 is related to the generalized pentagonal numbers A001318, A195310 and A000041. See comments in A195825.

%e Written as a triangle:

%e . 1;

%e . 1, 1;

%e . 2, 1;

%e . 3, 1;

%e . 4, 1, -1;

%e . 4, 2, -1;

%e . 5, 3, -1;

%e . 7, 4, -1;

%e . 10, 4, -2;

%e . 12, 4, -3;

%e . 13, 4, -4;

%e . 13, 5, -4;

%e . 14, 7, -4, -1;

%e . 16, 10, -4, -1;

%e . 21, 12, -5, -1;

%e . 27, 13, -7, -1;

%e . 32, 13, -10, -1;

%e . 34, 13, -12, -1, 1;

%Y Row sums give A195850.

%Y Cf. A001082, A175003, A195828, A195836, A195837, A195838, A195839.

%K sign,tabf

%O 1,9

%A _Omar E. Pol_, Sep 24 2011