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 A116267 Numbers k such that k*(k+4) gives the concatenation of two numbers m and m-3. 6
 8, 98, 426, 571, 725, 844, 998, 7808, 9998, 36363, 63634, 99998, 326732, 673265, 999998, 4545452, 5454545, 9999998, 47058821, 52941176, 99999998, 331983805, 332667332, 384615384, 422892896, 475524475, 524475522, 577107101, 615384613, 667332665, 668016192, 719964244 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Chai Wah Wu, Table of n, a(n) for n = 1..10000 PROG (Python) from itertools import count, islice from sympy import sqrt_mod def A116267_gen(): # generator of terms for j in count(0): b = 10**j a = b*10+1 for k in sorted(sqrt_mod(1, a, all_roots=True)): if a*(b+3) <= k**2-1 < a*(a+2): yield k-2 A116267_list = list(islice(A116267_gen(), 20)) # Chai Wah Wu, Feb 19 2024 CROSSREFS Cf. A116136, A116260, A116266, A116268, A116275. Sequence in context: A083182 A302277 A302727 * A183334 A196327 A116130 Adjacent sequences: A116264 A116265 A116266 * A116268 A116269 A116270 KEYWORD nonn,base AUTHOR Giovanni Resta, Feb 06 2006 EXTENSIONS a(29)-a(32) from Chai Wah Wu, Feb 19 2024 STATUS approved

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Last modified April 19 19:02 EDT 2024. Contains 371798 sequences. (Running on oeis4.)