A133102
Number of partitions of n^3 into n distinct nonzero squares.
Original entry on oeis.org
1, 0, 0, 0, 0, 3, 5, 20, 56, 112, 268, 618, 1922, 8531, 29021, 100407, 321531, 899618, 2937312, 9295401, 31615059, 117365818, 403433963, 1417579281, 4848439367, 15960316056, 55180971700, 190251417034, 670818005444, 2429973932322
Offset: 1
a(6) = 3 because there are 3 ways to express 6^3 = 216 as a sum of 6 distinct nonzero squares: 216 = 1^2 + 2^2 + 4^2 + 5^2 + 7^2 + 11^2 = 1^2 + 3^2 + 5^2 + 6^2 + 8^2 + 9^2 = 3^2 + 4^2 + 5^2 + 6^2 + 7^2 + 9^2.
Cf.
A133103 (number of ways to express n^3 as a sum of n nonzero squares),
A133105 (number of ways to express n^4 as a sum of n distinct nonzero squares).
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a(i, n, k)=local(s, j); if(k==1, if(issquare(n) && n
2 more terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Dec 16 2007
A133104
Number of partitions of n^4 into n nonzero squares.
Original entry on oeis.org
1, 0, 3, 1, 49, 732, 9659, 190169, 3225654, 61896383, 1360483727, 30969769918, 778612992660, 20749789703573, 579672756740101, 17115189938667708, 525530773660159970, 16825686497823918869, 561044904645283065043, 19368002907483932784642
Offset: 1
a(3)=3 because there are 3 ways to express 3^4 = 81 as a sum of 3 nonzero squares: 81 = 1^2 + 4^2 + 8^2 = 3^2 + 6^2 + 6^2 = 4^2 + 4^2 + 7^2.
a(4)=1 because the only way to express 4^4 = 256 as a sum of 4 nonzero squares is 256 = 8^2 + 8^2 + 8^2 + 8^2.
Cf.
A133105 (number of ways to express n^4 as a sum of n distinct nonzero squares),
A133103 (number of ways to express n^3 as a sum of n nonzero squares).
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a(i, n, k)=local(s, j); if(k==1, if(issquare(n), return(1), return(0)), s=0; for(j=ceil(sqrt(n/k)), min(i, floor(sqrt(n-k+1))), s+=a(j, n-j^2, k-1)); return(s)) for(n=1,50, m=n^4; k=n; print1(a(m, m, k)", ") ) \\ Herman Jamke (hermanjamke(AT)fastmail.fm), Dec 16 2007
a(9) from Herman Jamke (hermanjamke(AT)fastmail.fm), Dec 16 2007
Showing 1-2 of 2 results.