A353386 - OEIS

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A353386

Sums of two squares obtained by expanding a k X k matrix to (k+1) X (k+1) and taking the not yet seen squared distances of all positions in the matrix.

1, 2, 4, 5, 8, 9, 10, 13, 18, 16, 17, 20, 25, 32, 26, 29, 34, 41, 50, 36, 37, 40, 45, 52, 61, 72, 49, 53, 58, 65, 74, 85, 98, 64, 68, 73, 80, 89, 100, 113, 128, 81, 82, 90, 97, 106, 117, 130, 145, 162, 101, 104, 109, 116, 125, 136, 149, 164, 181, 200, 121, 122, 137, 146, 157, 170, 185, 202, 221, 242

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

The terms are a permutation of the positive terms of A001481.

LINKS

Table of n, a(n) for n=1..70.

EXAMPLE

The sequence can be viewed as a table with line lengths A047800(k+1) - A047800(k), in which the not yet seen sums of squares form a table line. The table starts:

1, 2,

4, 5, 8,

9, 10, 13, 18,

16, 17, 20, 25, 32,

26, 29, 34, 41, 50,

36, 37, 40, 45, 52, 61, 72,

49, 53, 58, 65, 74, 85, 98

PROG

(PARI) a353386(nmax)={my(v=vectorsmall(2*nmax^2)); for(n=1, nmax,

for(k=0, n, my(s=n^2+k^2); if(!v[s], print1(s, ", "); v[s]++)); print())};

a353386(11)

CROSSREFS