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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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS Antti Karttunen, Table of n, a(n) for n = 0..10082 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. 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 KEYWORD nonn AUTHOR Antti Karttunen, Oct 12 2015 STATUS approved

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Last modified March 23 21:59 EDT 2023. Contains 361452 sequences. (Running on oeis4.)