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A171369
Triangle read by rows, replace 2's with 3's in A169695.
0
1, 3, 3, 1, 3, 3, 3, 3, 1, 3, 3, 3, 3, 3, 3, 1, 3, 3, 3, 3, 3, 3, 3, 3, 1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3
OFFSET
1,2
COMMENTS
Given triangle A275437 (wrapped to contain n terms per row) or sequence A169695, replace 2's with 3's, other terms remain as is.
FORMULA
T(n,k) = 1 if n*(n-1)/2+k is a square, otherwise T(n,k) = 3.
EXAMPLE
First few rows of the triangle =
.
1;
3, 3;
1, 3, 3;
3, 3, 1, 3;
3, 3, 3, 3, 3;
1, 3, 3, 3, 3, 3;
3, 3, 3, 1, 3, 3, 3;
3, 3, 3, 3, 3, 3, 3, 1;
...
CROSSREFS
Sequence in context: A206400 A321129 A278265 * A111629 A083953 A066400
KEYWORD
nonn,easy,tabl
AUTHOR
Gary W. Adamson, Dec 06 2009
EXTENSIONS
Description corrected by Robert Israel, Jan 03 2019
STATUS
approved