A083811 Numbers n such that 2n+1 is the digit reversal of n+1.

36, 396, 3996, 39996, 399996, 3999996, 39999996, 399999996, 3999999996, 39999999996, 399999999996, 3999999999996

Offset: 1

Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 08 2003

Keywords

• base
• nonn

Comments

1. a(n) = 36 + 360 + 3600+ ...+ up to n terms. a(n) = sum of n terms of the geometric progression with the first term 36 and common ratio 10. 2. a(n) = 36*A000042(n).( the unary sequence).

Examples

			36 + 1 = 37, 2*36 + 1 = 73.
		

Crossrefs

Cf. A000042.

Formula

a(n) = 4*(10^n - 1).