A102718 a(n) = a(n-1) + (sum of the last two digits of the sequence so far); a(0)=0; a(1)=1.

0, 1, 2, 5, 12, 15, 21, 24, 30, 33, 39, 51, 57, 69, 84, 96, 111, 113, 117, 125, 132, 137, 147, 158, 171, 179, 195, 209, 218, 227, 236, 245, 254, 263, 272, 281, 290, 299, 317, 325, 332, 337, 347, 358, 371, 379, 395, 409, 418, 427, 436, 445, 454, 463, 472, 481, 490, 499, 517, 525, 532, 537, 547, 558, 571

Offset: 0

Author

Eric Angelini, Feb 06 2005

Keywords

• base
• easy
• nonn

Examples

			96 + (9 + 6) = 111;
111 + (1 + 1) = 113;
113 + (1 + 3) = 117.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A102039.

Programs

Mathematica

Join[{0,1,2,5},NestList[#+Total[Take[IntegerDigits[#],-2]]&,12,60]] (* Harvey P. Dale, May 11 2018 *)

PARI

first(n) = {n = max(n, 5); res = [0, 1, 2, 5, 12]; res = concat(res, vector(n - 5)); for(i = 6, min(n, 37), res[i] = res[i-1] + vecsum(digits(res[i-1] % 100)));
for(i = 38, n, res[i] = res[i - 20] + 200); res} \\ David A. Corneth, May 11 2018

Formula

a(n + 20) = 200 + a(n) for n > 17. - David A. Corneth, May 11 2018

Extensions

Corrected and extended by Harvey P. Dale, May 11 2018