



1, 1, 2, 2, 3, 5, 6, 6, 7, 7, 8, 10, 9, 11, 10, 12, 11, 13, 12, 14, 13, 17, 14, 18, 15, 19, 16, 20, 17, 23, 20, 28, 21, 29, 22, 30, 23, 31, 24, 32, 25, 33, 26, 34, 27, 35, 28, 36, 29, 37, 30, 38, 31, 39, 32, 40, 33, 41, 34, 42, 35, 43, 36, 44, 37, 45, 38, 46, 39, 47, 40, 48, 41
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OFFSET

1,3


COMMENTS

a(2n+2)>a(2n) and a(2n+1)>a(2n1), at least up through the 125th row.


LINKS

Table of n, a(n) for n=1..73.


MATHEMATICA

a[ 0, 0 ] = 1; a[ m_, n_ ] := a[ m, n ] = Block[ {p = Sort[ Flatten[ Join[ Table[ a[ i, j ], {i, 0, m  1}, {j, 0, i} ], Table[ a[ i, j ], {i, m, m}, {j, 0, n  1} ] ] ] ]}, k = Complement[ Range[ p[ [ 1 ] ] + 1 ], p ][ [ 1 ] ]; While[ Position[ p, k ] != {}  If[ n == 0, GCD[ k, a[ m  1, 0 ] ] != 1, If[ n == m, GCD[ k, a[ m  1, m  1 ] ] != 1, GCD[ k, a[ m  1, n ] ] != 1  GCD[ k, a[ m  1, n  1 ] ] != 1 ] ], k++ ]; k ]; t = Table[ Plus @@ (2Mod[ Table[ a[ m, n ], {n, 0, m} ], 2 ]  1), {m, 0, 75} ]; Table[ Plus @@ Take[ t, n ], {n, 73} ]


CROSSREFS

Cf. A097883, A098381.
Sequence in context: A225489 A308773 A051732 * A098180 A270875 A117752
Adjacent sequences: A098379 A098380 A098381 * A098383 A098384 A098385


KEYWORD

nonn


AUTHOR

Leroy Quet and Robert G. Wilson v, Sep 04 2004


STATUS

approved



