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 A263094 Squares in A236562; numbers n^2 such that there is at least one such k for which k - d(k) = n^2, where d(k) is the number of divisors of k (A000005). 3
 0, 1, 4, 9, 16, 81, 121, 144, 169, 225, 289, 361, 441, 529, 576, 625, 841, 900, 961, 1024, 1089, 1296, 1444, 1521, 1600, 1681, 1764, 1849, 1936, 2025, 2304, 2401, 2601, 2704, 2809, 3025, 3249, 3721, 3969, 4096, 4225, 4356, 4624, 4761, 4900, 5041, 5184, 5476, 5625, 5776, 5929, 6241, 6400, 6561, 6889, 7056, 7396, 7569, 7744, 8281, 8464, 8649, 9216, 9409, 9801, 10201, 10404, 11025 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Starting offset is zero, because a(0)=0 is a special case in this sequence. LINKS Antti Karttunen, Table of n, a(n) for n = 0..20763 FORMULA a(n) = A000290(A263092(n)). MATHEMATICA Take[Select[Sort@ DeleteDuplicates@ Table[n - DivisorSigma[0, n], {n, 20000}], IntegerQ@ Sqrt@ # &], 68] (* Michael De Vlieger, Oct 13 2015 *) PROG (PARI) \\ See code in A263092. (Scheme) (define (A263094 n) (A000290 (A263092 n))) CROSSREFS Cf. A000005, A049820, A060990. Intersection of A000290 and A236562. Cf. A263092 (gives the square roots of these terms). Cf. A263095 (complement among squares). Cf. A262514 (a subsequence). Cf. also A263090, A263098. Sequence in context: A296111 A038784 A038239 * A226354 A299921 A089149 Adjacent sequences:  A263091 A263092 A263093 * A263095 A263096 A263097 KEYWORD nonn AUTHOR Antti Karttunen, Oct 11 2015 STATUS approved

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Last modified October 14 17:31 EDT 2019. Contains 328022 sequences. (Running on oeis4.)