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A331395
Number of nonnegative integer matrices with total sum n, nonzero rows and distinct columns each with the same sum with columns in decreasing lexicographic order.
2
1, 3, 5, 21, 17, 281, 65, 3209, 10853, 47617, 1025, 3610317, 4097, 22361569, 570275061, 2515267681, 65537, 229801424781, 262145, 10805763650257, 114290395025669, 39654899669089, 4194305, 150858428803209493, 140094551951590929, 98672497472409697
OFFSET
1,2
COMMENTS
The condition that the columns be in decreasing order is equivalent to considering nonequivalent matrices with distinct columns up to permutation of columns.
LINKS
FORMULA
a(n) = Sum_{d|n} A331278(n/d, d).
a(p) = 2^(p-1) + 1 for prime p.
CROSSREFS
Cf. A331278.
Sequence in context: A103991 A224994 A321768 * A086175 A065926 A128561
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Jan 15 2020
STATUS
approved