A116205 Numbers k such that k concatenated with k+7 gives the product of two numbers which differ by 3.

1, 81, 1353, 3997, 7723, 23761, 26271, 76771, 1415683, 3890571, 8495497, 1066870443, 1239366513, 4198438981, 4534273891, 6502317141, 6918679731, 2199164200036329043, 2820114781174460091, 5500888421709400741

Offset

1,2

Comments

Also numbers k such that k concatenated with k+9 gives the product of two numbers which differ by 1.

Also numbers k such that k concatenated with k-3 gives the product of two numbers which differ by 7.

Is a(n) = A116179(n+1) for n>=2? - R. J. Mathar, May 22 2026

Links

Table of n, a(n) for n=1..20.

Crossrefs

Cf. A116179, A116172, A115429, A116173, A116193, A116336.

Cf. A116132, A116099, A116139, A116152, A116269, A116348.

Sequence in context: A059977 A231912 A382388 * A237455 A253488 A236738

Adjacent sequences: A116202 A116203 A116204 * A116206 A116207 A116208

Keyword

nonn,base

Author

Giovanni Resta, Feb 06 2006

Extensions

Edited by N. J. A. Sloane, Apr 13 2007

Status

approved