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A322081 Square array A(n,k), n >= 1, k >= 0, read by antidiagonals: A(n,k) = Sum_{d|n} (-1)^(n/d+1)*d^k. 5
1, 1, 0, 1, 1, 2, 1, 3, 4, -1, 1, 7, 10, 1, 2, 1, 15, 28, 11, 6, 0, 1, 31, 82, 55, 26, 4, 2, 1, 63, 244, 239, 126, 30, 8, -2, 1, 127, 730, 991, 626, 196, 50, 1, 3, 1, 255, 2188, 4031, 3126, 1230, 344, 43, 13, 0, 1, 511, 6562, 16255, 15626, 7564, 2402, 439, 91, 6, 2, 1, 1023, 19684, 65279, 78126, 45990, 16808, 3823, 757, 78, 12, -2 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,6
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..1275 (first 50 antidiagonals)
FORMULA
G.f. of column k: Sum_{j>=1} j^k*x^j/(1 + x^j).
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, ...
0, 1, 3, 7, 15, 31, ...
2, 4, 10, 28, 82, 244, ...
-1, 1, 11, 55, 239, 991, ...
2, 6, 26, 126, 626, 3126, ...
0, 4, 30, 196, 1230, 7564, ...
MATHEMATICA
Table[Function[k, Sum[(-1)^(n/d + 1) d^k, {d, Divisors[n]}]][i - n], {i, 0, 12}, {n, 1, i}] // Flatten
Table[Function[k, SeriesCoefficient[Sum[j^k x^j/(1 + x^j), {j, 1, n}], {x, 0, n}]][i - n], {i, 0, 12}, {n, 1, i}] // Flatten
PROG
(PARI) T(n, k)={sumdiv(n, d, (-1)^(n/d+1)*d^k)}
for(n=1, 10, for(k=0, 8, print1(T(n, k), ", ")); print); \\ Andrew Howroyd, Nov 26 2018
CROSSREFS
Sequence in context: A332864 A337569 A244891 * A279396 A161224 A147567
KEYWORD
sign,tabl
AUTHOR
Ilya Gutkovskiy, Nov 26 2018
STATUS
approved

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Last modified June 3 05:44 EDT 2024. Contains 373054 sequences. (Running on oeis4.)