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A157557 Half the number of length n integer sequences with sum zero and sum of squares 1250. 1
1, 3, 222, 7810, 245715, 7887621, 271336828, 9598223664, 323149486005, 9653120522639, 265199107509930, 6875831133411318, 170878889034103705, 4105071237469192095, 95749849725794169816, 2169082695217727013712 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,2
LINKS
FORMULA
[cache enabling] count(n,s,ss)->count(n,t,tt) where t=s mod n, q=(t-s)/n, tt=ss+2*q*s+n*q^2; count(n,t,tt)=sum[i^2<=tt]{ count(n-1,t-i,tt-i^2) }. a(n)=count(n,0,1250)/2.
CROSSREFS
Sequence in context: A140441 A261385 A071881 * A279532 A157582 A241098
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 02 2009
STATUS
approved

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Last modified June 18 12:25 EDT 2024. Contains 373481 sequences. (Running on oeis4.)