A116185
Numbers k such that k concatenated with k+4 gives the product of two numbers which differ by 3.
Original entry on oeis.org
150, 186, 324, 376, 666, 2046, 3000, 82650, 100384, 466716, 1322316, 4049584, 67820074, 110003884, 135734074, 156502836, 196043286, 213017754, 238849000, 261405396, 289940826, 310507774, 365294050, 398891964, 446667216
Offset: 1
-
cc:=proc(x,y) local s: s:=proc(m) nops(convert(m,base,10)) end: x*10^s(y)+y: end: a:=proc(n) if type(sqrt(9+4*cc(n,n+4)),integer) then n else fi end: seq(a(n),n=1..500000); # very slow; cc yields the concatenation of x and y; - Emeric Deutsch, May 05 2007
A116330
Numbers k such that k*(k+3) gives the concatenation of two numbers m and m+6.
Original entry on oeis.org
4, 85, 76982, 714689, 952313, 90438190, 96320543, 32980078899028, 34346653774237, 42816188292272, 42881990066487, 57118009933511, 57183811707726, 65653346225761, 67019921100970, 81321742742209
Offset: 1
96320543 * 96320546 = 92776472//92776478, where // denotes concatenation.
A116322
Numbers k such that k*(k+1) gives the concatenation of two numbers m and m+5.
Original entry on oeis.org
41, 59, 32262233, 67737767, 79321057, 3341093417798787499094, 3861488851737861033962, 4747922651210186579788, 5252077348789813420212, 6138511148262138966038, 6658906582201212500906, 7232275368591793618232
Offset: 1
79321057 * 79321058 = 62918301//62918306, where // denotes concatenation.
A116343
Numbers k such that k*(k+1) gives the concatenation of two numbers m and m+8.
Original entry on oeis.org
14, 86, 76983, 714690, 952314, 90438191, 96320544, 32980078899029, 34346653774238, 42816188292273, 42881990066488, 57118009933512, 57183811707727, 65653346225762, 67019921100971, 81321742742210
Offset: 1
96320544 * 96320545 = 92776472//92776480, where // denotes concatenation.
Showing 1-4 of 4 results.
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