Some strange mathematical sequences are always whole numbers — until they’re not. The puzzling patterns have revealed ties to graph theory and prime numbers, awing mathematicians.

One of the two animals ended up, on average, more likely to form novel recursive sequences than about three-quarters of the preschoolers and roughly half of the Bolivian villagers.

A multi-institutional research team found the cognitive ability to represent recursive sequences occurs in humans and non-human primates across age, education, culture and species.

Remarkably, the birds performed just as well as the children, producing recursive sequences in around 40% of trials without needing the additional training required by the monkeys.

YULIN CAO, G. LADAS, SYMMETRIC PERIODIC SOLUTIONS OF RATIONAL RECURSIVE SEQUENCES, The Rocky Mountain Journal of Mathematics, Vol. 25, No. 1 (WINTER 1995), pp. 133-143 ...

During training, the crows received birdseed pellets or mealworms for successfully forming recursive sequences, per the Wall Street Journal.

Here we present a new scheme for understanding the structural features and potential mathematical rules of symmetrical DNA sequences using a method containing stepwise classification and recursive ...

Since these involve complex thought patterns, the researchers initially assumed that the monkeys would have less pronounced recursive abilities. Learning symbol sequences ...

Recursive splicing depends on juxtaposed 3′ and 5′ splice-site sequences, called recursive splice sites, in the middle of long introns (Fig. 1a).