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A220556 Table T(n,k) = ((n+k-1)*(n+k-2)/2+n)^k, n,k >0 read by antidiagonals. 1
1, 4, 3, 64, 25, 6, 2401, 512, 81, 10, 161051, 20736, 2197, 196, 15, 16777216, 1419857, 104976, 6859, 400, 21, 2494357888, 148035889, 7962624, 390625, 17576, 729, 28, 500246412961, 21870000000, 887503681, 33554432, 1185921, 39304, 1225, 36 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column number k of the table T(n,k) is formula for Cantor antidiagonal order in power k

LINKS

Boris Putievskiy, Table of n, Rows n = 1 to 30 of triangle, flattened

Boris Putievskiy, Transformations Integer Sequences And Pairing Functions arXiv:1212.2732 [math.CO]

FORMULA

As a linear array, the sequence is a(n) = n^A004763 or a(n) = n^((t*t+3*t+4)/2 - n), where t=floor[(-1+sqrt(8*n-7))/2].

EXAMPLE

The start of the sequence as triangle array is:

1;

4,3;

64,25,6;

2401,512,91,10;

161051,20736,2197,196,15;

. . .

PROG

(Python)

t=int((math.sqrt(8*n-7) - 1)/ 2)

m=n**((t*t+3*t+4)/2-n)

CROSSREFS

Cf. A004736.

Sequence in context: A013335 A298314 A299389 * A299188 A300026 A266255

Adjacent sequences:  A220553 A220554 A220555 * A220557 A220558 A220559

KEYWORD

nonn,tabl

AUTHOR

Boris Putievskiy, Dec 16 2012

STATUS

approved

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Last modified December 3 20:56 EST 2020. Contains 338920 sequences. (Running on oeis4.)