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 A181319 Numbers n with property that there is a different number m such that the lunar squares n*n and m*m are the same. 4
 11011, 11012, 11013, 11014, 11015, 11016, 11017, 11018, 11019, 11021, 11022, 11023, 11024, 11025, 11026, 11027, 11028, 11029, 11031, 11032, 11033, 11034, 11035, 11036, 11037, 11038, 11039, 11041, 11042, 11043, 11044, 11045, 11046, 11047, 11048, 11049, 11051, 11052, 11053, 11054, 11055, 11056, 11057, 11058 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS David Applegate and N. J. A. Sloane, Table of n, a(n) for n = 1..21894 D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing] EXAMPLE 11011*11011 = 11111*11111 = 111111111, so 11011 and 11111 are members. PROG (ksh script from David Applegate; assumes the dismal C program dismal2a has been installed) i=0 while [ \$i -lt 100000 ]; do   echo \$i \$(dismal2a -d mul \$i \$i)   i=\$((\$i+1)) done | awk '{   nrt[\$2]++;   rt[\$2]=rt[\$2] " " \$1; } END{   for (i in rt)     if (nrt[i] > 1)       print i, rt[i]; }' | sort -k1, 1n > dismal_multsquares.txt CROSSREFS Cf. A087019, A180513. Sequence in context: A267038 A267293 A300557 * A267811 A267934 A218598 Adjacent sequences:  A181316 A181317 A181318 * A181320 A181321 A181322 KEYWORD nonn,base AUTHOR David Applegate and N. J. A. Sloane, Jan 26 2011 STATUS approved

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Last modified December 15 01:20 EST 2018. Contains 318141 sequences. (Running on oeis4.)