A202266 Composite numbers in which all substrings and reversal substrings are composites.

4, 6, 8, 9, 44, 46, 48, 49, 64, 66, 68, 69, 84, 86, 88, 94, 96, 99, 444, 446, 448, 464, 466, 468, 469, 484, 486, 488, 494, 496, 644, 646, 648, 649, 664, 666, 668, 669, 684, 686, 688, 694, 696, 699, 844, 846, 848, 849, 864, 866, 868, 869, 884, 886, 888, 946, 948

Offset

1,1

Comments

Subsequence of A202265, A202262.

Links

Table of n, a(n) for n=1..57.

Example

All substrings and reversal substrings of 446 are composites: 4, 6, 44, 46, 64, 446, 644.

Crossrefs

Cf. A202263 (primes in which all substrings and reversal substrings are primes), A202264 (noncomposite numbers in which all substrings and reversal substrings are noncomposite), A202265 (nonprimes in which all substrings and reversal substrings are nonprimes).

Sequence in context: A113591 A029581 A202262 * A232541 A076612 A182775

Adjacent sequences: A202263 A202264 A202265 * A202267 A202268 A202269

Keyword

nonn,base

Author

Jaroslav Krizek, Dec 25 2011

Status

approved