A115429
Numbers k such that the concatenation of k with k+8 gives a square.
Original entry on oeis.org
6001, 6433, 11085116, 44496481, 96040393, 115916930617, 227007035017, 274101929528, 434985419768, 749978863753, 996004003993, 1365379857457948, 1410590590957816, 1762388551055953, 2307340946901148, 2700383162251217
Offset: 1
6001//6009 = 7747^2, where // denotes concatenation.
96040393//96040400 = 98000200 * 98000202.
96040393//96040397 = 98000199 * 98000203.
96040393//96040392 = 98000198 * 98000204.
Cf.
A030465,
A102567,
A115426,
A115437,
A115428,
A115430,
A115431,
A115432,
A115433,
A115434,
A115435,
A115436,
A115440.
A116193
Numbers k such that k concatenated with k+5 gives the product of two numbers which differ by 5.
Original entry on oeis.org
11, 45, 18281, 32769, 56891, 180689, 330539, 959481, 1850201, 3247409, 4940219, 2425563239, 2575561739, 6003563495, 7245212645, 7770160145, 4983798265289, 5049762270381, 5534298528989, 5603798594169, 21894082450101
Offset: 1
7770160145//7770160136 = 8814851183 * 8814851192, where // denotes concatenation.
A116114
Numbers k such that k concatenated with k-7 gives the product of two numbers which differ by 9.
Original entry on oeis.org
13, 493, 607, 629, 757, 17927, 33247, 93869, 19467217, 31223879, 72757727, 13454739732766891651472740499, 40093333713615672956030023507, 48089152118689474641229584727, 66424317743191484432891678269
Offset: 1
A116240
n times n+9 gives the concatenation of two numbers m and m-8.
Original entry on oeis.org
93, 454, 538, 993, 7664, 9993, 72720, 99993, 356428, 643564, 999993, 9090909, 9999993, 35294117, 64705875, 99999993, 335664328, 664335664, 684210519, 818181818, 838056673, 846153846, 866028701, 980125138, 999999993
Offset: 1
Showing 1-4 of 4 results.
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