A176660 Partial sums of A038772.

23, 50, 79, 113, 150, 188, 231, 277, 324, 373, 426, 480, 536, 593, 651, 710, 777, 845, 914, 987, 1061, 1137, 1215, 1294, 1377, 1463, 1550, 1639, 1733, 1830, 1928, 2131, 2338, 2547, 2770, 2997, 3226, 3459, 3698, 3945, 4194, 4447, 4704, 4963, 5226, 5493

Offset

1,1

Comments

Partial sums of numbers not divisible by any of their digits. The partial sums of the complement (A038770, numbers divisible by at least one of their digits) is A176659. Hence the sum of the two partial sums (properly offset) is triangular numbers A000217. The subsequence of primes in the partial sum begins: 23, 79, 113, 277, 373, 593, 1061, 1733, 2131, 4447, 9479. The smallest square in the sequence is 324.

Links

Table of n, a(n) for n=1..46.

Formula

a(n) = SUM[i=1..n] A038772(i).

Example

a(4) = 23 + 27 + 29 + 34 = 113 is prime.

Crossrefs

Cf. A038772, 034709, A034837, A038769, A038770, A176659.

Sequence in context: A132764 A029493 A063321 * A185187 A157095 A281266

Adjacent sequences: A176657 A176658 A176659 * A176661 A176662 A176663

Keyword

base,easy,nonn

Author

Jonathan Vos Post, Apr 23 2010

Status

approved