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A048149 Array T read by diagonals: T(i,j) = number of pairs (h,k) with h^2+k^2 <= i^2+j^2, h>=0, k >= 0. 10
1, 3, 3, 6, 4, 6, 11, 8, 8, 11, 17, 13, 9, 13, 17, 26, 19, 15, 15, 19, 26, 35, 28, 22, 20, 22, 28, 35, 45, 37, 30, 26, 26, 30, 37, 45, 58, 48, 39, 33, 31, 33, 39, 48, 58, 73, 62, 52, 43, 41, 41, 43, 52, 62, 73, 80, 75, 64, 54, 50, 48, 50, 54 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..62.

EXAMPLE

Diagonals (each starting on row 1): {1}; {3,3}; {6,4,6}; ...

MATHEMATICA

t[i_, j_] := Module[{h, k}, Reduce[h^2 + k^2 <= i^2 + j^2 && h >= 0 && k >= 0, {h, k}, Integers] // ToRules // Length[{##}]&]; Table[t[n-k, k], {n, 0, 10}, {k, 0, n}] // Flatten (* Jean-François Alcover, Nov 26 2013 *)

CROSSREFS

T(n, n)=A000603.

Sequence in context: A051472 A257957 A324000 * A155169 A144624 A023827

Adjacent sequences:  A048146 A048147 A048148 * A048150 A048151 A048152

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling

EXTENSIONS

a(55) corrected by Jean-François Alcover, Nov 26 2013

STATUS

approved

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Last modified November 17 01:05 EST 2019. Contains 329209 sequences. (Running on oeis4.)