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A263087
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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).
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7
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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
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OFFSET
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0,1
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LINKS
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Antti Karttunen, Table of n, a(n) for n = 0..10082
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FORMULA
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a(n) = A060990(n^2) = A060990(A000290(n)).
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PROG
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(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)))
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CROSSREFS
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Cf. A000005, A000290, A002182, A002183, A060990.
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
Adjacent sequences: A263084 A263085 A263086 * A263088 A263089 A263090
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KEYWORD
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nonn
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AUTHOR
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Antti Karttunen, Oct 12 2015
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STATUS
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approved
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