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A263087
a(n) = A060990(n^2); number of solutions to x - d(x) = n^2, where d(x) is the number of divisors of x (A000005).
7
2, 2, 1, 1, 1, 0, 0, 0, 0, 2, 0, 1, 2, 1, 0, 1, 0, 1, 0, 1, 0, 2, 0, 1, 2, 1, 0, 0, 0, 1, 1, 2, 1, 1, 0, 0, 2, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 2, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 2, 3, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0
OFFSET
0,1
LINKS
FORMULA
a(n) = A060990(n^2) = A060990(A000290(n)).
PROG
(PARI)
A060990(n) = { my(k = n + 2400, s=0); while(k > n, if(((k-numdiv(k)) == n), s++); k--; ); s}; \\ Hard limit A002183(77)=2400 good for at least up to A002182(77) = 10475665200.
A263087(n) = A060990(n^2);
for(n=0, 10082, write("b263087.txt", n, " ", A263087(n)));
(Scheme) (define (A263087 n) (A060990 (A000290 n)))
CROSSREFS
Cf. A263093 (positions of zeros), A263092 (nonzeros).
Cf. A263250, A263251 (bisections) and A263252, A263253 (their partial sums).
Cf. also A261088, A263088.
Sequence in context: A123550 A320638 A262045 * A204433 A004578 A319372
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 12 2015
STATUS
approved