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A140648
Triangle T(n,m) which can create A140642 without help of Jacobsthal numbers.
0
1, 2, 0, 4, 1, 0, 8, 2, 0, 1, 16, 4, 1, 0, 2, 32, 8, 2, 0, 1, 4, 64, 16, 4, 1, 0, 2, 8, 128, 32, 8, 2, 0, 1, 4, 16, 256, 64, 16, 4, 1, 0, 2, 8, 32, 512, 128, 32, 8, 2, 0, 1, 4, 16, 64
OFFSET
0,2
COMMENTS
This triangle T(.,.) provides the additional terms if A140642 is constructed with a Pascal-type recurrence: A140642(n+1,m+1) = A140642(n,m) + A140642(n,m+1) + T(n,m+1).
Note almost odd palindromes (of squares) followed by their double.
Examples: 40=16+20+4, 42=20+21+1, 43=21+22+0, 44=22+24+2.
FORMULA
Southeast diagonals based on A131577 (which is also in A140531). First preceded with 1, 0. Second with 2, 1, 0. Tends towards even palindromes, second part being A131577. Verticals: A000079, A131577, (0, A131577), ... .
EXAMPLE
Triangle begins:
1;
2, 0;
4, 1, 0;
8, 2, 0, 1;
16, 4, 1, 0, 2;
32, 8, 2, 0, 1, 4;
64, 16, 4, 1, 0, 2, 8;
128, 32, 8, 2, 0, 1, 4, 16;
CROSSREFS
Cf. A083329 (row sums).
Sequence in context: A255330 A291940 A153345 * A153342 A144258 A056859
KEYWORD
nonn,tabl,uned
AUTHOR
Paul Curtz, Jul 09 2008
STATUS
approved